Step 3 · 8–10%

Nervous System & Special Senses

Stroke, seizure, headache, memory, nerves, plus the eye and the ear.

Stroke & TIA

Last known well decides everything: image fast, give a lytic or pull the clot when eligible, then find the source and prevent the next event.

Rules to know

Sudden focal deficit, last known well < 4.5 h → noncontrast CT and glucose, then IV tenecteplase or alteplase if the deficit is disabling; other labs first only if coagulopathy suspected
Suspected large vessel occlusion (aphasia, gaze deviation, dense hemiparesis) → CT angiography with the first CT; thrombectomy up to 24 h for ICA, M1 or basilar occlusion, including selected large cores
Eligible for both a lytic and thrombectomy → give the lytic and move straight to thrombectomy; never wait to see whether the lytic works
Wake-up stroke or onset 4.5–9 h ago → lytic only with imaging selection: MRI diffusion-FLAIR mismatch or salvageable tissue on perfusion imaging
Minor nondisabling deficit or high-risk TIA (ABCD2 ≥ 4) → aspirin plus loaded clopidogrel within 24 h for 21 days, then one antiplatelet; no lytic
Blood pressure before a lytic → bring below 185/110 with labetalol, nicardipine or clevidipine, then keep below 180/105 for 24 h
Ischemic stroke with no reperfusion therapy → permissive hypertension; treat only above 220/120 during the first 48–72 h
Headache, vomiting or worse deficit during a lytic → stop the infusion, emergent CT, fibrinogen level; cryoprecipitate and tranexamic acid if bleeding
TIA → within 24 h: MRI with diffusion, CTA or carotid duplex, ECG and telemetry, echo, A1c and lipids; admit if that cannot happen fast
Symptomatic carotid stenosis 70–99% → endarterectomy within 2 weeks; 50–69% individualized by age, sex and surgical risk; under 50% or occluded → medical therapy only
Stroke or TIA with atrial fibrillation → DOAC over warfarin, started within days (earlier for small infarcts) with no heparin bridge
Cryptogenic stroke after standard workup → 30-day ambulatory monitor or implantable loop recorder to find paroxysmal AF
Cryptogenic stroke, age ≤ 60, with a PFO → percutaneous closure plus antiplatelet when the shunt is large or an atrial septal aneurysm is present
After any ischemic stroke → antiplatelet, high-intensity statin to LDL < 70, BP < 130/80, quit smoking, diabetes control, regular exercise
Neck pain, Horner syndrome and stroke after minor neck strain → cervical artery dissection; CTA or MRA, then antiplatelet or anticoagulant
Thunderclap headache → noncontrast CT; negative scan within 6 h of onset excludes SAH; later or unclear → LP for xanthochromia or CTA
Aneurysmal SAH → ICU, nimodipine for 21 days, systolic < 160 until the aneurysm is coiled or clipped (ideally within 24 h), drain for hydrocephalus
SAH day 3–14 with new deficit or drowsiness → vasospasm; transcranial Doppler or CTA, keep euvolemic, induced hypertension, endovascular rescue
Spontaneous intracerebral hemorrhage → lower systolic toward 140 (not below 130) promptly, reverse anticoagulants, ICU or stroke unit, repeat CT for expansion
Hemorrhage on warfarin → 4-factor PCC plus IV vitamin K; on apixaban or rivaroxaban → 4-factor PCC; on dabigatran → idarucizumab
Cerebellar hemorrhage > 3 cm, brainstem compression or hydrocephalus → emergency surgical evacuation
Lobar bleeds or cortical microbleeds in an older adult → cerebral amyloid angiopathy; high rebleed risk, weigh every antithrombotic carefully
Headache, seizures, papilledema postpartum or on estrogen → cerebral venous sinus thrombosis; MR or CT venography; anticoagulate even with hemorrhagic infarction
Severe hypertension with confusion, seizures, cortical blindness, posterior white-matter edema → PRES; lower MAP no more than 25% in the first hour, remove triggers
Stroke with fever and a new murmur → septic emboli from endocarditis; blood cultures and echo; no lytic and no anticoagulant
Stroke under 50 without vascular risk factors → look for dissection, PFO, cocaine or amphetamine use, antiphospholipid antibodies, sickle cell disease
Any acute stroke → bedside swallow screen before food, drink or oral pills
Admitted acute stroke → stroke unit, glucose 140–180, treat fever, pneumatic compression for DVT prevention, early mobilization and rehab
Dizziness or arm pain with arm exercise, unequal arm pressures → subclavian steal; duplex or CTA; revascularize only if symptomatic

Traps that cost points

Waiting for INR and platelets before a lytic in a patient on no anticoagulant→ Only glucose must come first; wait for coagulation results only when anticoagulant use or a bleeding disorder is suspected, so treatment is not delayed.
Starting aspirin within 24 h after thrombolysis→ Hold all antithrombotics for 24 h after a lytic and repeat brain imaging before starting them.
Pushing systolic below 140 after successful thrombectomy→ Intensive lowering after reperfusion worsened function in trials; keep systolic under 180 and avoid aggressive drops.
Full-dose heparin to prevent early recurrence after ischemic stroke→ Early heparin adds bleeding without benefit; give antiplatelets, and when AF is the cause start a DOAC within days.
A DOAC for AF-related stroke in a patient with a mechanical valve→ Mechanical valves and moderate-to-severe mitral stenosis need warfarin; DOACs are contraindicated there.
Sending a TIA patient home with clinic follow-up in a few weeks→ Stroke risk peaks in the first 48 h; finish imaging and vessel studies within 24 h and start antiplatelet therapy now.
Thrombectomy for every distal branch occlusion→ Benefit is proven for ICA, M1 and basilar occlusions; recent trials in medium and distal branch occlusions showed no benefit.
Fluid-restricting hyponatremia after subarachnoid hemorrhage→ It is usually cerebral salt wasting; restriction causes hypovolemia and worsens vasospasm. Give isotonic or hypertonic saline.
Lumbar puncture first for a thunderclap headache→ Get noncontrast CT first; an early negative scan makes LP unnecessary and imaging first avoids puncturing over a mass.

Seizures & epilepsy

In the Brain

Stop status quickly, decide whether a first seizure needs a drug, match the drug to the epilepsy and the patient, and counsel on pregnancy and driving.

Rules to know

Convulsion ≥ 5 min or repeated without recovery → status epilepticus; airway, glucose check, IV lorazepam (repeat once) or IM midazolam 10 mg if no IV
Status continuing after two benzodiazepine doses → full IV load of levetiracetam, fosphenytoin or valproate (equally effective)
Status persisting after a second-line load → intubate, continuous midazolam or propofol infusion, continuous EEG in the ICU
Convulsions stopped but not waking within 20–30 min → urgent EEG for nonconvulsive status
First unprovoked seizure, back to baseline → glucose, sodium, calcium, magnesium, toxicology, pregnancy test, then EEG and brain MRI; CT in the ED if focal or traumatic
Single unprovoked seizure with normal EEG and MRI → usually no drug; treat if EEG is epileptiform, a lesion is seen, prior brain injury or nocturnal seizure
Provoked seizure (hypoglycemia, hyponatremia, alcohol withdrawal, drug toxicity) → correct the cause; no long-term antiseizure drug
Two unprovoked seizures > 24 h apart → epilepsy; start one drug at low dose and titrate
Focal epilepsy → lamotrigine or levetiracetam first; oxcarbazepine or carbamazepine are alternatives
Generalized epilepsy → valproate works best, but avoid it in anyone who could become pregnant; lamotrigine or levetiracetam instead
Child with many brief daily staring spells → absence epilepsy if hyperventilation provokes them and EEG shows 3-Hz spike-wave; ethosuximide first
Teen with morning myoclonic jerks and convulsions after sleep loss → juvenile myoclonic epilepsy; levetiracetam or valproate, usually lifelong
Lamotrigine → slow titration over weeks; any rash means stop (Stevens-Johnson risk, higher with valproate)
Carbamazepine in Asian ancestry → test HLA-B*15:02 first; watch sodium, white count and hormonal contraceptive failure
Levetiracetam with irritability, depression or suicidal thoughts → known adverse effect; screen mood and switch drugs
Phenytoin → gingival overgrowth, hirsutism, bone loss; nystagmus and ataxia mean toxicity; adjust the level for low albumin
Topiramate → kidney stones, word-finding trouble, weight loss, metabolic acidosis, acute angle-closure glaucoma
Enzyme-inducing antiseizure drug and wants contraception → IUD or injectable; pill, patch and ring may fail
Epilepsy and planning pregnancy → move off valproate, prefer lamotrigine or levetiracetam, daily folic acid before conception; never stop drugs abruptly
Pregnant on lamotrigine → clearance rises and levels fall; check levels each trimester and raise dose, reduce after delivery
Brief generalized seizure with fever, age 6 months–5 years → simple febrile seizure if back to normal; find the fever source, no EEG, imaging or routine LP
Febrile seizure with meningeal signs or persistent lethargy → lumbar puncture; consider it too when Hib or pneumococcal vaccines are incomplete
Febrile seizure counseling → about one in three recur; fever-lowering drugs do not prevent recurrence; later epilepsy is uncommon
Long spells with eyes shut and side-to-side head shaking → psychogenic nonepileptic seizures (pelvic thrusting, waxing course); video-EEG, then CBT
Lateral tongue bite and prolonged confusion afterward → seizure; a few jerks with rapid recovery fit convulsive syncope
Weakness after a seizure resolving within 48 h → Todd paralysis; image if it persists or stroke is possible
Seizures despite two appropriate drugs at adequate doses → drug-resistant epilepsy; refer to an epilepsy center for surgical evaluation
Seizure-free ≥ 2 years with normal EEG → discuss slow taper, weighing recurrence and driving loss
Driving after a seizure → no driving until seizure-free for the interval set by state law (often 3–12 months); document the counseling
Frequent convulsive seizures → discuss sudden unexpected death in epilepsy; better control and nighttime supervision lower risk

Traps that cost points

Phenytoin or carbamazepine for absence or myoclonic seizures→ Both can worsen generalized absence and myoclonic seizures; use ethosuximide, valproate or levetiracetam.
Valproate for a young woman with generalized epilepsy→ Valproate causes neural tube defects and lower childhood IQ; choose lamotrigine or levetiracetam unless pregnancy is truly impossible.
A third or fourth benzodiazepine dose for ongoing status→ After two doses, load a second-line drug; more benzodiazepine adds respiratory depression without control.
Daily antiseizure drug after a simple febrile seizure→ Risks outweigh benefits; reassure, treat the fever source and teach parents how to keep the child safe during a seizure.
Ruling out epilepsy because a routine EEG was normal→ Interictal EEG is often normal; repeat with sleep deprivation or prolonged recording when history fits.
Running IV phenytoin fast without a monitor→ Rapid phenytoin causes hypotension and arrhythmia; use fosphenytoin or slow infusion with cardiac monitoring.
Stopping the antiseizure drug when pregnancy is discovered→ Uncontrolled convulsions harm mother and fetus; continue the drug, optimize dose and folic acid, and plan with obstetrics.

Headache

In the Brain

Spot the red flags that need imaging, treat migraine early and prevent it when frequent, and never miss giant cell arteritis or raised pressure.

Rules to know

Headache with any red flag → image: thunderclap, new after 50, progressive, positional, worse with Valsalva, fever, focal deficit, papilledema, cancer, immunosuppression, pregnancy
Recurrent typical migraine with normal neurologic exam → clinical diagnosis; no imaging
Mild to moderate migraine attack → NSAID or acetaminophen taken early, plus an antiemetic for nausea
Moderate to severe migraine → triptan early, ideally with an NSAID; avoid triptans in coronary or cerebrovascular disease and uncontrolled hypertension
Migraine with vascular disease or triptan failure → gepant (ubrogepant, rimegepant) or lasmiditan; no driving for 8 h after lasmiditan
Migraine in the ED → IV metoclopramide or prochlorperazine with diphenhydramine, fluids, ketorolac; dexamethasone cuts early recurrence; avoid opioids
Migraine ≥ 4 headache days a month or disabling attacks → offer prevention: propranolol, topiramate, amitriptyline, venlafaxine, candesartan, or a CGRP-targeted drug
CGRP-targeted prevention (erenumab, fremanezumab, galcanezumab, eptinezumab, atogepant) → acceptable first-line; erenumab can cause constipation and raise BP
Chronic migraine (≥ 15 headache days a month) → onabotulinumtoxinA or CGRP-targeted drug, and treat any medication overuse
Near-daily headache with frequent acute medication use → medication overuse headache (analgesics ≥ 15 or triptans ≥ 10 days a month); limit the overused drug, start prevention
Migraine with aura → avoid estrogen-containing contraception; progestin-only methods or IUD
Migraine in pregnancy → acetaminophen and metoclopramide first, sumatriptan if needed; avoid valproate, topiramate, ergots, and NSAIDs late in pregnancy
Predictable menstrual migraine → short perimenstrual course of a long-acting triptan (frovatriptan) or NSAID
Bilateral pressing band headache without nausea → tension-type; NSAID or acetaminophen; amitriptyline if frequent
Nightly attacks of one-sided orbital pain with tearing and restlessness → cluster headache; 100% oxygen 12–15 L/min by mask or subcutaneous sumatriptan
Cluster prevention → verapamil with ECGs as the dose rises; short steroid course or occipital nerve block bridges until it works
Obese young woman, daily headache, brief visual dimming, pulsatile tinnitus, papilledema → MRI with MR venography, then LP with opening pressure
Idiopathic intracranial hypertension → weight loss and acetazolamide, formal visual fields; falling vision → nerve sheath fenestration, shunt or venous stenting
Over 50, new headache, jaw claudication, scalp tenderness, high ESR or CRP → giant cell arteritis; prednisone 40–60 mg that day, then biopsy or temporal artery ultrasound
Giant cell arteritis with vision loss → IV methylprednisolone and urgent ophthalmology; tocilizumab to spare steroids
Electric jabs of facial pain from chewing or touch → trigeminal neuralgia; carbamazepine or oxcarbazepine; MRI for MS or vessel compression
Repeated thunderclap headaches over days, postpartum or after serotonergic or vasoactive drugs → reversible cerebral vasoconstriction; CTA beading, stop triggers, avoid triptans
Headache after LP or epidural, relieved lying flat → post-dural puncture headache; fluids, caffeine, analgesics; epidural blood patch if it persists
Weekend or late-morning headache in a heavy coffee drinker → caffeine withdrawal; steady intake or slow taper
Seconds-long stabbing jabs, normal exam → primary stabbing headache; reassure, indomethacin if frequent
Strictly one-sided headache with tearing that responds only to indomethacin → paroxysmal hemicrania or hemicrania continua

Traps that cost points

Opioids or butalbital for recurrent migraine→ They drive medication overuse and chronic headache and work worse than triptans, gepants or antiemetic cocktails.
Antibiotics for recurrent sinus headache with a normal exam→ Most recurrent sinus-pressure headaches without purulent drainage or fever are migraine; treat as migraine.
Waiting for temporal artery biopsy before steroids→ Vision loss can occur within days; start steroids now. Biopsy stays diagnostic for about 2 weeks on treatment.
LP first in a patient with papilledema→ Image first to exclude a mass or venous thrombosis; LP over a mass can cause herniation.
Combined estrogen pill for a woman with migraine with aura→ Estrogen adds ischemic stroke risk in migraine with aura; use progestin-only methods, an IUD or barrier methods.
Requiring several older preventives to fail before a CGRP-targeted drug→ Current headache-society guidance treats CGRP-targeted agents as a first-line prevention option.
Oral triptan for a cluster attack→ Attacks peak too fast for pills; use high-flow oxygen or subcutaneous or nasal triptans.
Treating idiopathic intracranial hypertension without visual field checks→ Vision loss is the main danger; track perimetry and escalate to surgery if fields worsen.

Delirium, dementia & coma

In the Brain

Acute confusion is delirium until proven otherwise; find its cause. Chronic decline needs reversible causes excluded, the type named and behavior handled without harm.

Rules to know

Acute fluctuating inattention and confusion in an older inpatient → delirium; hunt the cause: drugs, infection, urinary retention, constipation, pain, hypoxia, electrolytes, withdrawal
Delirium workup → medication review first, vitals, oxygen saturation, glucose, CBC, BMP, calcium, urinalysis, ECG; head imaging only with focal signs, fall or anticoagulation
Delirium care → treat the cause, reorient, glasses and hearing aids, daylight and night sleep, early mobility, family at bedside; avoid restraints and catheters
Delirium with agitation endangering the patient → brief low-dose haloperidol or quetiapine; stop once safe; antipsychotics do not shorten delirium
Delirium in Parkinson disease or Lewy body dementia needing a drug → low-dose quetiapine; avoid haloperidol and other strong D2 blockers
Quiet, drowsy, withdrawn older inpatient → hypoactive delirium; same workup; often missed and carries worse prognosis
Older inpatient at risk of delirium → prevention bundle (orientation, sleep, mobility, hydration, sensory aids); routine prophylactic antipsychotics not recommended
Coma of unclear cause → airway, glucose, thiamine, naloxone if opioid signs, CT head, then labs, toxicology and EEG for nonconvulsive status
Memory complaint → Mini-Cog or MoCA, depression screen, hearing and vision, B12, TSH, CBC, metabolic panel, one brain MRI or CT
Cognitive decline with independence preserved → mild cognitive impairment; yearly recheck, exercise, vascular risk control; no cholinesterase inhibitor
Gradual memory loss with lost independence → Alzheimer dementia; donepezil, rivastigmine or galantamine; add memantine when moderate to severe
Cholinesterase inhibitor → nausea, diarrhea, vivid dreams, bradycardia and syncope; check pulse, avoid with heart block
MCI or mild Alzheimer dementia considering anti-amyloid antibody → confirm amyloid (PET, CSF or validated blood test), APOE genotype, baseline MRI, scheduled MRIs
Headache, confusion or seizure on anti-amyloid antibody → ARIA; hold the infusion and get MRI
Visual hallucinations, fluctuating alertness, parkinsonism, dream enactment → Lewy body dementia; cholinesterase inhibitor; severe antipsychotic sensitivity
Personality change, disinhibition, apathy, compulsive eating in the 50s with memory spared → frontotemporal dementia; SSRIs for behavior; cholinesterase inhibitors do not help
Stepwise decline, focal signs, vascular risk factors → vascular dementia; control BP, lipids and diabetes, antiplatelet when indicated
Dementia progressing over weeks with myoclonus → Creutzfeldt-Jakob disease; MRI diffusion, CSF RT-QuIC, EEG; supportive care, notify public health
Apparent dementia with low mood and poor effort → depression with cognitive impairment (many I-don't-know answers); treat depression, then retest
Agitation, wandering or resisting care in dementia → look for pain, constipation, infection, retention, environmental triggers; caregiver strategies before drugs
Dangerous agitation or psychosis in dementia despite those steps → lowest-dose antipsychotic briefly after discussing higher mortality and stroke; plan a taper
Depression in dementia → sertraline or citalopram; avoid tricyclics and paroxetine
Dementia patient on diphenhydramine, oxybutynin or a benzodiazepine → deprescribe; anticholinergic and sedative load worsens cognition
New dementia diagnosis → plan early while the patient can take part: advance directives, finances, driving, home safety, caregiver support
Delirium or dementia facing a treatment choice → assess capacity for that specific decision; it may return as delirium clears

Traps that cost points

Calling new evening confusion in an older inpatient sundowning→ New or fluctuating confusion is delirium until proven otherwise; search for drugs, infection, retention and metabolic causes.
Lorazepam for an agitated delirious patient→ Benzodiazepines prolong and worsen delirium; reserve them for alcohol or sedative withdrawal.
Haloperidol for hallucinations in Lewy body dementia→ Strong D2 blockade can cause severe rigidity and a neuroleptic malignant picture; use a cholinesterase inhibitor and, if needed, low-dose quetiapine or pimavanserin.
Physical restraints for a wandering confused inpatient→ Restraints increase injury, delirium and pressure sores; use sitters, bed alarms and reorientation.
Ordering APOE testing to diagnose Alzheimer disease→ APOE is not diagnostic; use it only to estimate ARIA risk before anti-amyloid therapy.
Starting donepezil for mild cognitive impairment→ Cholinesterase inhibitors do not prevent progression in MCI and add side effects; focus on exercise and vascular risk.
Labeling gait trouble, incontinence and slowing as Alzheimer disease→ That triad suggests normal pressure hydrocephalus; get MRI and a large-volume tap test before settling the diagnosis.
Anti-amyloid antibody in a patient on full anticoagulation→ ARIA with hemorrhage is more dangerous on anticoagulants; most programs exclude them.

Meningitis, encephalitis & brain abscess

In the Brain

Antibiotics within the hour, cover Listeria at the age extremes, give acyclovir on suspicion, and know which immunocompromised lesion is which.

Rules to know

Fever, headache, stiff neck or altered mental status → blood cultures, then LP; empiric antibiotics within 1 hour, never held for imaging or LP
Suspected meningitis with immunocompromise, papilledema, focal deficit, new seizure or depressed consciousness → cultures, dexamethasone and antibiotics first, then CT, then LP if safe
Adult 18–50 with suspected bacterial meningitis → ceftriaxone plus vancomycin plus dexamethasone
Bacterial meningitis over 50, pregnant, alcohol use or immunocompromised → add ampicillin for Listeria
Neonate under 1 month with meningitis → ampicillin plus gentamicin or cefotaxime; ceftriaxone avoided in neonates
Meningitis after neurosurgery, shunt or penetrating head trauma → vancomycin plus cefepime, ceftazidime or meropenem
Dexamethasone for meningitis → give just before or with the first antibiotic dose; continue 4 days only if pneumococcal (or Hib in children)
CSF neutrophils, glucose < 40 or ratio < 0.4, high protein → bacterial; lymphocytes with normal glucose → viral; lymphocytes with low glucose → TB or fungal
Close contact of meningococcal disease (household, daycare, exposed to secretions) → single-dose ciprofloxacin, rifampin, or ceftriaxone (ceftriaxone in pregnancy) within 24 h
Meningococcal meningitis admitted → droplet precautions until 24 h of effective antibiotics
Lymphocytic meningitis with normal glucose in a well patient → usually enterovirus; supportive care, stop empiric antibiotics when cultures are negative
Fever, confusion, behavior change, seizures, temporal lobe signal → HSV encephalitis; IV acyclovir now, MRI, CSF HSV PCR; repeat PCR if early test negative
IV acyclovir → hydrate well and follow creatinine for crystal nephropathy
Young woman with psychiatric change, then seizures, dyskinesias, autonomic swings → anti-NMDA receptor encephalitis; CSF antibodies, pelvic imaging for teratoma, immunotherapy
Summer fever with encephalitis or flaccid limb weakness in an older adult → West Nile virus; CSF IgM, supportive care
Ring-enhancing lesion with headache and deficit, dental, sinus or ear source → brain abscess; no LP, aspirate if > 2.5 cm, ceftriaxone plus metronidazole 6–8 weeks
AIDS, CD4 < 100, multiple ring-enhancing basal ganglia lesions, Toxoplasma IgG positive → pyrimethamine, sulfadiazine, leucovorin; biopsy if no improvement in 2 weeks
Progressive deficits with nonenhancing white-matter lesions, immunosuppressed → PML (AIDS, natalizumab, rituximab); CSF JC virus PCR; restore immunity
HIV with CD4 < 100, headache, fever, high opening pressure → cryptococcal meningitis; CSF antigen, amphotericin plus flucytosine then fluconazole, repeat LPs for pressure
Cryptococcal meningitis with new HIV diagnosis → delay ART 4–6 weeks to avoid immune reconstitution
Subacute meningitis with basilar enhancement, cranial nerve palsies, hydrocephalus → TB meningitis; four-drug therapy plus dexamethasone
Reactive syphilis serology plus neurologic, eye or ear symptoms → LP for CSF VDRL; IV penicillin G 10–14 days, desensitize if allergic; ocular disease treated the same
Lyme facial palsy, meningitis or radiculitis → oral doxycycline works as well as IV ceftriaxone
Immigrant with new seizure and cystic lesions showing a scolex → neurocysticercosis; albendazole plus steroids for live cysts, antiseizure drug; calcified only → antiseizure drug alone
Bat in a sleeper's room or wild carnivore bite → rabies prophylaxis: wash wound, rabies immune globulin, vaccine on days 0, 3, 7, 14
Trismus and painful spasms after a dirty wound → tetanus; tetanus immune globulin, vaccine, metronidazole, debridement, benzodiazepines, ICU
Aseptic meningitis after NSAIDs, TMP-SMX, IVIG or lamotrigine → drug-induced; stop the drug
Recurrent bacterial meningitis → look for a CSF leak after skull fracture, or complement deficiency (CH50) if Neisseria recurs

Traps that cost points

Head CT before antibiotics in every patient with suspected meningitis→ Most need no CT before LP; when CT is indicated, draw cultures and give dexamethasone and antibiotics first.
Ceftriaxone and vancomycin alone in a 70-year-old→ Older adults and the immunocompromised need ampicillin for Listeria, which cephalosporins do not cover.
Holding acyclovir until HSV PCR returns→ Delay worsens outcome; start acyclovir on suspicion and stop only after a negative PCR plus an alternative explanation.
LP in a patient with a brain abscess→ Mass effect risks herniation and CSF rarely shows the organism; get blood cultures and aspirate the abscess instead.
Prophylaxis for every staff member on the ward after a meningococcal admission→ Only those with direct secretion exposure, such as unmasked intubation or suctioning, need prophylaxis.
Starting ART the same week as cryptococcal meningitis treatment→ Early ART raised mortality from immune reconstitution; wait 4–6 weeks after antifungal therapy begins.
Giving dexamethasone hours after antibiotics have started→ Benefit depends on giving it before or with the first dose; late steroids add little.
Steroids before biopsy for a single enhancing lesion in AIDS with negative Toxoplasma IgG→ Lymphoma is likely; steroids can shrink it and spoil the biopsy, so obtain tissue first when feasible.

Neuromuscular disease, neuropathy & nerve pain

In the Brain

Watch breathing in weakness, name the junction or nerve from the pattern, and treat neuropathic pain without opioids.

Rules to know

Ascending symmetric weakness and lost reflexes after diarrhea or a viral illness → Guillain-Barré; admit, LP (high protein, normal cells), nerve conduction studies
Guillain-Barré → serial FVC and NIF; ICU and intubation if FVC < 20 mL/kg, NIF weaker than −30 cm H2O, or bulbar weakness
Guillain-Barré unable to walk or worsening → IVIG or plasma exchange (equal, not combined); steroids do not help
Guillain-Barré on the ward → watch for arrhythmias and BP swings, give DVT prophylaxis, treat back and limb pain
Ophthalmoplegia, ataxia and areflexia after infection → Miller Fisher variant; anti-GQ1b antibodies
Fatigable ptosis and double vision, worse by evening → myasthenia gravis; acetylcholine receptor antibodies (MuSK if negative), then chest CT for thymoma
Myasthenia symptoms → pyridostigmine; generalized disease adds prednisone or a steroid-sparing agent
Generalized AChR-positive myasthenia under 65, or any thymoma → thymectomy
Refractory generalized myasthenia → complement inhibitor (vaccinate against meningococcus first) or FcRn blocker
Myasthenic crisis (dyspnea, weak cough, dysphagia) → ICU, serial FVC and NIF, IVIG or plasma exchange; intubate early
Myasthenia patient needing a drug → avoid aminoglycosides, fluoroquinolones, macrolides, IV magnesium, beta-blockers and checkpoint inhibitors
Proximal weakness that improves with repeated effort, dry mouth, low reflexes → Lambert-Eaton; calcium-channel antibodies, CT chest for small cell cancer
Descending paralysis with dilated pupils after home-canned food → botulism; antitoxin through the health department before confirmation, monitor breathing
Floppy infant with constipation and weak suck after honey → infant botulism; botulism immune globulin, admit
Upper and lower motor neuron signs with fasciculations, no sensory loss → ALS; EMG; riluzole, edaravone, tofersen if SOD1 mutation
ALS with orthopnea or falling FVC → noninvasive ventilation; feeding tube before FVC falls below 50%; early goals-of-care talks
Diabetes → yearly monofilament foot exam; painful neuropathy → pregabalin, gabapentin, duloxetine or a tricyclic; avoid opioids
Distal symmetric neuropathy of unclear cause → A1c or glucose tolerance test, B12 with methylmalonic acid, serum protein electrophoresis with immunofixation
Lost position sense, ataxia and spasticity with B12 risk → subacute combined degeneration (metformin, nitrous oxide, vegan diet); replace B12 even without anemia
Isoniazid, vincristine, metronidazole, linezolid → neuropathy; pyridoxine prevents it with isoniazid
Night numbness of thumb, index and middle fingers → carpal tunnel; neutral wrist splint, steroid injection; nerve studies and release if weakness or atrophy
Numb ring and little fingers, worse with elbow bent → ulnar neuropathy at the elbow; avoid leaning, padding, night splint
Foot drop with weak eversion, normal inversion → peroneal palsy at the fibular head (leg crossing, weight loss); weak inversion too → L5 radiculopathy
Wrist drop after sleeping with an arm over a chair → radial nerve compression; cock-up splint, usually recovers
Acute one-sided facial weakness including the forehead → Bell palsy; prednisone within 72 h, antiviral optional if severe, eye lubrication and taping
Facial weakness sparing the forehead → central lesion; stroke workup
Facial palsy with ear vesicles → Ramsay Hunt; antiviral plus steroid; bilateral facial palsy → Lyme disease, sarcoidosis or Guillain-Barré
Pain > 3 months after shingles → postherpetic neuralgia; lidocaine patch, gabapentinoid or tricyclic; prevent with recombinant zoster vaccine
Burning pain, swelling, color and sweating change after injury or fracture → complex regional pain syndrome; early physical and occupational therapy
Boy with calf enlargement, Gowers sign, CK in the thousands → Duchenne dystrophy; genetic testing, corticosteroids, heart and lung monitoring
Cannot release grip, frontal balding, cataracts → myotonic dystrophy; yearly ECG for conduction block
Sudden flaccid weakness after a carbohydrate meal, low potassium, thyrotoxic → periodic paralysis; cautious potassium, propranolol, treat the thyroid

Traps that cost points

Waiting for low oxygen saturation to intubate in Guillain-Barré or myasthenia→ Hypoxemia comes late in neuromuscular failure; decide on FVC, NIF, cough and bulbar function.
Steroids for Guillain-Barré→ Steroids do not help and may slow recovery; give IVIG or plasma exchange.
Excluding Guillain-Barré because the first-week CSF protein is normal→ Protein often rises only after the first week; diagnose clinically and with nerve studies.
Ciprofloxacin or gentamicin for infection in a myasthenia patient→ Both block neuromuscular transmission and can trigger crisis; choose another class.
Folic acid alone for macrocytic anemia with neuropathy→ Folate corrects the blood count but lets B12 nerve damage progress; check and replace B12.
MRI and labs for every typical Bell palsy→ Typical cases need steroids and eye care only; investigate if atypical, recurrent or no recovery by 3 months.
Opioids for painful diabetic neuropathy→ Use gabapentinoids, SNRIs or tricyclics; opioids add risk without durable benefit.

Multiple sclerosis & spinal cord

In the Brain

Image the whole cord fast when a sensory level appears, treat compression before it becomes paraplegia, and start MS disease-modifying therapy early.

Rules to know

Young adult with optic neuritis, internuclear ophthalmoplegia, numbness or Lhermitte sign → suspect MS; MRI brain and spine with gadolinium
MS diagnosis → lesions separated in space and time on MRI; CSF oligoclonal bands can substitute for time; exclude B12 deficiency, NMOSD, syphilis, lupus
MS relapse with functional loss → check for infection first, then methylprednisolone 1 g daily for 3–5 days; plasma exchange if no response
Old MS symptoms flaring with fever, heat or infection → pseudo-relapse; treat the trigger, no steroids
Relapsing MS or isolated syndrome with typical MRI lesions → start disease-modifying therapy early; high-efficacy agents increasingly used first
Anti-CD20 therapy (ocrelizumab, ofatumumab) → hepatitis B screen and vaccines beforehand; infusion reactions, infections, low immunoglobulins
Natalizumab → JC virus antibody testing; PML risk rises with positive serology, > 2 years of use, prior immunosuppressants
Fingolimod or siponimod → first-dose heart rate monitoring, eye exam for macular edema, varicella immunity before starting
Teriflunomide → teratogenic and persists for years; accelerated elimination before conception; monitor liver tests
Primary progressive MS → ocrelizumab is the approved disease-modifying drug
MS spasticity → baclofen or tizanidine with PT; bladder urgency → post-void residual, then antimuscarinic or mirabegron; fatigue → exercise
MS and pregnancy → relapses fall during pregnancy and rise after delivery; plan when to stop and restart therapy
Painful eye movement, central vision loss, red desaturation, afferent pupil defect → optic neuritis; MRI brain for MS risk; high-dose steroids speed recovery
Severe optic neuritis with long-segment myelitis → NMOSD when myelitis spans ≥ 3 segments or hiccups and vomiting persist; AQP4 and MOG antibodies
Bilateral leg weakness, sensory level, urinary retention → emergency MRI spine to exclude compression; inflammatory myelitis → high-dose steroids
Known cancer, back pain worse lying down, then weakness or sensory level → dexamethasone now, emergent whole-spine MRI, then radiation or surgery
Saddle anesthesia, urinary retention, bilateral sciatica, weak anal tone → cauda equina syndrome; emergent lumbar MRI and surgical decompression
Fever and back pain with IV drug use or diabetes, then deficits → spinal epidural abscess; MRI with gadolinium, blood cultures, vancomycin plus cefepime or ceftriaxone, drainage
Older adult after neck hyperextension with arms weaker than legs → central cord syndrome
Paraplegia with spared vibration after aortic surgery → anterior spinal artery infarct: motor and pain loss, posterior columns intact
Penetrating cord hemisection → Brown-Séquard: same-side weakness and position loss, opposite-side pain and temperature loss
Cape-like loss of pain and temperature with hand weakness → syringomyelia, often with Chiari I; MRI cervical spine and brain
Acute traumatic cord injury → immobilize, keep MAP 85–90 for about a week, avoid hypotension; no high-dose steroids
Cord injury with hypotension and bradycardia → neurogenic shock; fluids, then vasopressors, atropine for bradycardia
Injury above T6 with sudden severe hypertension, headache, flushing above the level → autonomic dysreflexia; sit up, loosen clothes, drain bladder, check bowel
Older adult with clumsy hands, gait change, hyperreflexia, Hoffmann sign → cervical spondylotic myelopathy; MRI and surgical referral
Chronic cord injury → intermittent catheterization, bowel program, skin checks for pressure injury, DVT prophylaxis early on
MS walking impairment → dalfampridine; avoid with seizures or creatinine clearance ≤ 50

Traps that cost points

High-dose methylprednisolone for acute traumatic spinal cord injury→ No functional benefit and more infections; focus on perfusion pressure, immobilization and early decompression when indicated.
Lumbar MRI only for suspected malignant cord compression→ Metastases are often multilevel; image the whole spine.
Holding dexamethasone until the MRI is done in a cancer patient with weakness→ Give dexamethasone as soon as compression with deficits is suspected; it does not alter the scan.
Steroids for an MS flare during a urinary infection→ Fever and infection unmask old deficits; treat the infection and reassess before calling it a relapse.
Interferon or natalizumab for NMOSD→ Several MS drugs worsen NMOSD; confirm AQP4 status and use NMOSD-specific therapy.
Waiting for a second attack before MS therapy→ Early disease-modifying therapy after a typical first attack with MRI lesions reduces relapses and disability.
Discharging new urinary retention with back pain without imaging→ Retention with back pain or saddle numbness is cauda equina until an emergent MRI says otherwise.

Eye

In the Brain

Sort the red eye that needs an ophthalmologist today, treat sudden painless vision loss as a stroke, and know which drops help and which harm.

Rules to know

Red eye with pain, reduced vision or photophobia → same-day ophthalmology; also for corneal opacity or a fixed pupil
Painful red eye, halos, fixed mid-dilated pupil, hard globe → acute angle closure; timolol, apraclonidine, pilocarpine, IV acetazolamide, then laser iridotomy both eyes
Angle-closure triggers → dim light, anticholinergics, sympathomimetics, topiramate; avoid dilating eyes known to have narrow angles
Painless gradual peripheral field loss, cupped optic discs → open-angle glaucoma; prostaglandin analog drops or laser trabeculoplasty
Sudden painless monocular blindness, cherry-red spot, pale retina → central retinal artery occlusion; stroke-center evaluation now, ESR and CRP if over 50, carotid and cardiac workup
Brief monocular vision loss like a curtain, now resolved → amaurosis fugax; same urgent workup as a TIA
Sudden painless vision loss with diffuse retinal hemorrhages → central retinal vein occlusion; ophthalmology, anti-VEGF for macular edema, control BP and glucose
Flashes, a shower of floaters, then a curtain → retinal detachment; same-day ophthalmology for repair
Type 2 diabetes → dilated eye exam at diagnosis, then yearly (every 1–2 years if normal and well controlled); type 1 → within 5 years of onset
Diabetic macular edema or proliferative retinopathy → intravitreal anti-VEGF; panretinal laser for proliferative disease
Older smoker with central distortion on Amsler grid → macular degeneration; wet form → urgent anti-VEGF; intermediate dry form → AREDS2 vitamins, stop smoking
Gradual glare, night halos, dim red reflex → cataract; surgery when it limits daily function
Watery red eye, tender preauricular node, recent cold → viral conjunctivitis; cool compresses, hand hygiene, no antibiotics
Purulent discharge with lids stuck shut in the morning → bacterial conjunctivitis; erythromycin ointment or polymyxin-trimethoprim drops
Red painful eye in a contact lens wearer → stop lenses, topical fluoroquinolone for Pseudomonas; corneal infiltrate → same-day ophthalmology
Sudden copious purulent discharge in a sexually active adult → gonococcal conjunctivitis; IM ceftriaxone, ophthalmology, treat chlamydia too
Itchy bilateral watery eyes with seasonal allergies → topical antihistamine with mast-cell stabilizer (olopatadine)
Branching dendrite on fluorescein → HSV keratitis; topical or oral antiviral, ophthalmology; never a topical steroid
Forehead zoster with vesicles on the nasal tip → zoster ophthalmicus; oral antiviral now and urgent ophthalmology
Foreign-body sensation with fluorescein uptake → corneal abrasion; topical antibiotic (fluoroquinolone for lens wearers), no patch, no anesthetic drops to take home
Chemical splash → irrigate at once and copiously until pH is neutral, before checking acuity; then ophthalmology
Penetrating injury, teardrop pupil, low eye pressure → open globe; rigid shield, no pressure or tonometry, IV antibiotics, antiemetic, tetanus, CT orbits, surgery
Blood layering in the anterior chamber after trauma → hyphema; head up, shield, avoid NSAIDs, sickle screen, ophthalmology
Lid swelling plus painful eye movements, proptosis or vision change → orbital cellulitis; CT orbits, admit for IV vancomycin plus ceftriaxone; lid only → preseptal, oral antibiotics
Photophobia, ring of redness at the limbus, cells in anterior chamber → anterior uveitis; ophthalmology for steroid and cycloplegic drops; look for HLA-B27 disease, sarcoid, IBD
Painful red lid bump → hordeolum, warm compresses; recurrent firm painless lid lump in an older adult → biopsy to exclude sebaceous carcinoma
Ptosis and miosis with neck pain → carotid dissection; CTA or MRA now; in a smoker with shoulder pain → chest imaging for apical tumor
Third nerve palsy with a dilated pupil → posterior communicating aneurysm; emergent CTA; pupil-sparing in a diabetic → ischemic, observe and recheck
Ethambutol → optic neuropathy, baseline and monthly acuity and red-green testing; long-term steroids → cataract and glaucoma; amiodarone → corneal deposits
White pupillary reflex in a child → retinoblastoma until proven otherwise; urgent ophthalmology
Constant eye misalignment after 4–6 months of age → refer; untreated strabismus causes amblyopia, treatable best before school age
Painless bright red patch on the white of the eye, normal vision → subconjunctival hemorrhage; reassure; check BP and anticoagulation if recurrent

Traps that cost points

Prescribing steroid eye drops for a red eye→ Steroid drops worsen HSV keratitis and fungal ulcers and raise eye pressure; leave them to the ophthalmologist.
Sending home anesthetic drops for a corneal abrasion→ Repeated topical anesthetic delays healing and causes corneal melt; use oral analgesics and a topical antibiotic.
Measuring pH or acuity before irrigating a chemical injury→ Every second counts with alkali; irrigate first, then examine.
Booking a routine eye appointment for central retinal artery occlusion→ It is an ocular stroke; send to a stroke center for immediate evaluation and secondary prevention.
Patching a contact lens wearer's abrasion→ Patching favors Pseudomonas keratitis; leave it open, use fluoroquinolone drops and recheck within 24 h.
Pressing on or measuring pressure in a suspected ruptured globe→ Pressure can extrude eye contents; shield it and get emergency ophthalmology.
Dilating drops for a patient with an anatomically narrow angle→ Dilation can trigger acute angle closure; screen with history and ophthalmology input first.
Observing a pupil-involving third nerve palsy as diabetic→ A dilated pupil points to compression by an aneurysm; get emergent vascular imaging.

Movement disorders

In the Brain

Recognize parkinsonism and tremor types, give levodopa without fear, and avoid the drugs that make movement disorders worse.

Rules to know

Asymmetric rest tremor, slowness, rigidity, reduced arm swing → Parkinson disease; clinical diagnosis, imaging only if atypical
Parkinson disease limiting function → levodopa-carbidopa, the most effective first-line drug at any age
Younger patient with mild Parkinson symptoms → MAO-B inhibitor or dopamine agonist can come first; levodopa also acceptable
Dopamine agonist (pramipexole, ropinirole) → ask every visit about gambling, shopping, hypersexuality, sleep attacks, hallucinations, leg edema
Levodopa wearing off before the next dose → shorter intervals, add a COMT inhibitor (entacapone, opicapone) or MAO-B inhibitor
Peak-dose dyskinesias → smaller, more frequent levodopa doses or amantadine
Disabling motor fluctuations with good levodopa response and no dementia → deep brain stimulation referral
Hallucinations in Parkinson disease → remove anticholinergics and amantadine, reduce agonists; then pimavanserin or quetiapine, clozapine if refractory
Nausea in Parkinson disease → avoid metoclopramide and prochlorperazine; ondansetron with QT awareness
Parkinson patient admitted or made NPO → give levodopa on schedule (tube if needed); abrupt stop risks a malignant hyperthermia-like crisis
Orthostatic dizziness in Parkinson disease → reduce antihypertensives, more salt and fluid, compression; midodrine, droxidopa or fludrocortisone
Parkinsonism with early backward falls and vertical gaze palsy → progressive supranuclear palsy; with early autonomic failure → multiple system atrophy; both respond poorly to levodopa
Symmetric parkinsonism on an antipsychotic, metoclopramide or prochlorperazine → drug-induced; stop or switch the drug rather than add levodopa
Twisted neck or upward-fixed eyes soon after a D2 blocker → acute dystonia; IV or IM diphenhydramine or benztropine
Bilateral action tremor of hands, head or voice → essential tremor (family history, eased by alcohol); propranolol or primidone
Disabling essential tremor despite drugs → deep brain stimulation or focused ultrasound thalamotomy
New fine postural tremor → check TSH, caffeine, and drugs such as lithium, valproate, beta-agonists and SSRIs
Chorea, psychiatric change and cognitive decline with an affected parent → Huntington disease; CAG repeat testing after genetic counseling
Huntington chorea → tetrabenazine, deutetrabenazine or valbenazine (monitor mood) or an antipsychotic; screen for suicide often
Healthy minor at risk for Huntington disease → defer predictive testing until the child can decide as an adult
Evening urge to move the legs, relieved by moving → restless legs; check ferritin and transferrin saturation; iron if ferritin ≤ 75 or saturation < 20%
Restless legs needing a drug → gabapentin, gabapentin enacarbil or pregabalin first; dopamine agonists avoided long term (augmentation)
Restless legs worsening → stop sedating antihistamines, dopamine-blocking antiemetics, antipsychotics and serotonergic antidepressants where possible; think CKD, pregnancy
Motor and vocal tics for > 1 year starting in childhood → Tourette disorder; behavioral therapy first, guanfacine or clonidine, aripiprazole if severe
Young patient with tremor or dystonia plus liver disease or psychiatric change → Wilson disease; ceruloplasmin, 24-h urine copper, slit-lamp exam
Adult with sustained involuntary neck turning, no drug exposure → cervical dystonia; botulinum toxin injections

Traps that cost points

Delaying levodopa to save it for later→ Delay does not prevent future dyskinesia; give levodopa when symptoms limit function.
Haloperidol or metoclopramide for a Parkinson patient→ Dopamine blockers sharply worsen parkinsonism; use quetiapine, pimavanserin or ondansetron instead.
Holding levodopa while a Parkinson patient is NPO→ Abrupt withdrawal can cause rigidity, fever and rhabdomyolysis; continue by tube or use alternative routes.
Propranolol for essential tremor in a patient with asthma→ Nonselective beta-blockade can trigger bronchospasm; use primidone.
Trihexyphenidyl for tremor in a 75-year-old→ Anticholinergics cause confusion, retention and constipation in older adults; avoid them.
Long-term pramipexole for restless legs→ Dopamine agonists cause augmentation; correct iron and use gabapentinoids first.
Missing iron deficiency in restless legs→ Low iron stores worsen symptoms; check ferritin and transferrin saturation and replace iron.

Head injury, raised pressure & brain tumors

In the Brain

Know who needs a head CT, manage concussion return safely, treat raised pressure without harm, and work up a brain mass in the right order.

Rules to know

Head injury, GCS 13–15 → CT only with risk features: age ≥ 65, vomiting ≥ 2, skull fracture signs, dangerous mechanism, amnesia ≥ 30 min, GCS < 15 at 2 h
Head injury on an anticoagulant or with a bleeding disorder → CT even when well
Athlete with suspected concussion → out of play that day; no same-day return
Concussion recovery → 24–48 h relative rest, early light aerobic activity, then stepwise return to school and sport, each step ≥ 24 h symptom-free
Symptoms > 4 weeks after concussion → persistent post-concussive symptoms; targeted vestibular, neck or cognitive therapy, screen mood, avoid prolonged rest
Lucid interval then decline after a temporal blow, lens-shaped bleed → epidural hematoma; emergency neurosurgical evacuation
Crescent-shaped bleed in an older or alcohol-using patient → subdural hematoma; evacuate if > 10 mm thick, > 5 mm shift or declining; reverse anticoagulants
Older adult with weeks of headache, confusion or falls → chronic subdural; burr-hole drainage if symptomatic; middle meningeal artery embolization lowers recurrence
Severe TBI (GCS ≤ 8) → intubate, avoid hypoxia and systolic < 110, head up 30°, normocapnia, ICP monitoring, levetiracetam or phenytoin for 7 days
Raised ICP: morning headache, vomiting, papilledema, Cushing triad → head of bed 30°, mannitol or hypertonic saline, neurosurgery; hyperventilation only as a brief bridge
Brain edema → dexamethasone helps vasogenic edema from tumor or abscess; no role in traumatic or stroke edema
Blown pupil, contralateral weakness, falling consciousness → uncal herniation; osmotic therapy now and emergency neurosurgery
Comatose after cardiac arrest → targeted temperature control and fever prevention; no prognosis before 72 h after normothermia; combine exam, EEG, SSEP, MRI
Adult with new seizure, headache or deficit → MRI with contrast; multiple lesions at gray-white junction → metastases, CT chest, abdomen and pelvis for primary
Brain metastases → dexamethasone for edema, antiseizure drug only after a seizure; single lesion → surgery plus radiosurgery; several → radiosurgery
Ring-enhancing mass crossing the corpus callosum → glioblastoma; maximal safe resection, radiation plus temozolomide; survival often under 2 years
Dural-based enhancing mass with dural tail → meningioma; observe small asymptomatic ones with serial MRI, resect if symptomatic or growing
HIV with CD4 < 50, periventricular lesion, EBV DNA in CSF → primary CNS lymphoma; avoid steroids before biopsy; high-dose methotrexate
Child with morning vomiting, headache and unsteady gait → posterior fossa tumor (medulloblastoma, pilocytic astrocytoma); MRI
Café-au-lait spots, axillary freckles, neurofibromas → NF1; yearly eye exam for optic glioma, BP checks for renal artery stenosis or pheochromocytoma
Bilateral vestibular schwannomas → NF2; hearing and MRI surveillance, screen relatives
Ash-leaf spots, infantile spasms, facial angiofibromas → tuberous sclerosis; renal angiomyolipoma and cardiac rhabdomyoma surveillance
V1 port-wine stain with seizures → Sturge-Weber; MRI and glaucoma screening
Cerebellar hemangioblastomas, renal cell cancer, pheochromocytoma → von Hippel-Lindau; lifelong tumor surveillance
Gait apraxia, urinary incontinence, then cognitive slowing → normal pressure hydrocephalus; MRI shows large ventricles; large-volume tap test predicts shunt benefit
Occipital headache with cough or strain, downbeat nystagmus → Chiari I malformation; MRI, decompression if symptomatic or syrinx

Traps that cost points

Prolonged hyperventilation to control raised ICP→ Low CO2 causes vasoconstriction and ischemia; use it only briefly while osmotic therapy and surgery are arranged.
Steroids for traumatic brain injury→ Steroids increased mortality in head injury trials; reserve dexamethasone for tumor-related edema.
Same-day return to the game once symptoms settle→ Any suspected concussion means no return that day; a second hit before recovery can be catastrophic.
Weeks of strict dark-room rest after concussion→ Prolonged rest slows recovery; after a day or two, gradual light aerobic activity helps.
Dexamethasone before biopsy of a suspected CNS lymphoma→ Steroids can melt lymphoma and make the biopsy nondiagnostic; hold them unless herniation threatens.
Prophylactic antiseizure drug for a brain tumor without seizures→ Prophylaxis does not prevent first seizures and adds side effects; start a drug only after a seizure.
Declaring poor prognosis on day 1 after cardiac arrest→ Sedation and cooling confound the exam; wait at least 72 h after normothermia and use several tests.

Ear, hearing & vertigo

In the Brain

Treat ear infections by age and severity, know when hearing loss is urgent, and separate harmless inner-ear vertigo from a posterior stroke.

Rules to know

Ear pain with a bulging red tympanic membrane → acute otitis media; high-dose amoxicillin
Nonsevere otitis media with reliable follow-up → observation 48–72 h is an option at age ≥ 2, or one-sided at 6–23 months; antibiotic if not improving
Otitis media after recent or failed amoxicillin → amoxicillin-clavulanate; also when conjunctivitis coexists
Otitis media with nonsevere penicillin allergy → cefdinir, cefuroxime or cefpodoxime
Recurrent otitis media with persistent effusion → tympanostomy tube referral (3 episodes in 6 months or 4 in a year)
Painless fluid behind the eardrum → otitis media with effusion; watchful waiting 3 months, hearing test if it persists, tubes if hearing loss
Pain on pulling the tragus, swollen canal after swimming → otitis externa; fluoroquinolone ear drops (safe if eardrum perforated), wick if canal closed
Older diabetic with severe ear pain, canal granulation tissue, facial palsy → necrotizing otitis externa; CT or MRI, IV antipseudomonal antibiotic, ENT
Swollen tender mastoid with the ear pushed forward after otitis → mastoiditis; CT, IV antibiotics, ENT drainage
Painless foul drainage with a retraction pocket of keratin debris → cholesteatoma; ENT for surgical removal
Painful swollen auricle after high cartilage piercing → perichondritis; antipseudomonal fluoroquinolone; drain any hematoma to prevent deformity
Symptomatic cerumen impaction → softening drops, irrigation or manual removal; avoid irrigation with perforation or tubes
Button battery in ear or nose → emergency removal; live insect → kill with mineral oil or lidocaine, then remove
Traumatic eardrum perforation → keep dry, most heal in weeks; ENT if vertigo, facial weakness or not healed by 2–3 months
Weber to the affected ear with bone conduction louder → conductive loss; Weber to the good ear with air louder → sensorineural loss
Sudden one-sided sensorineural hearing loss → audiometry, oral or intratympanic steroids within 2 weeks, MRI for vestibular schwannoma
Asymmetric sensorineural loss or one-sided tinnitus → MRI of the internal auditory canals with gadolinium
Older adult with gradual bilateral high-frequency loss → presbycusis; audiology and hearing aids (over-the-counter for mild to moderate)
Young adult with conductive loss worsening in pregnancy → otosclerosis; audiometry, hearing aid or stapes surgery
Notch at 4 kHz after loud exposure → noise-induced loss; hearing protection, avoid further exposure
Aminoglycosides, cisplatin, loop diuretics, high-dose salicylates → ototoxic; baseline and serial audiometry with prolonged use
Pulsatile tinnitus → vascular cause possible; imaging (CTA or MRA) and check for IIH
Seconds of vertigo with head turns, positive Dix-Hallpike → BPPV; Epley maneuver; no imaging and no long-term meclizine
Days of constant vertigo, one-direction nystagmus, abnormal head impulse, normal hearing → vestibular neuritis; brief antivestibular drug, vestibular rehab; with hearing loss → labyrinthitis
Acute vertigo with central signs → posterior circulation stroke: normal head impulse, direction-changing nystagmus, skew deviation or cannot walk; MRI with diffusion
Hours-long vertigo attacks with fluctuating hearing loss → Ménière disease (low-frequency loss, tinnitus, ear fullness); salt restriction, diuretic, ENT
Motion sickness before travel → scopolamine patch or meclizine; avoid scopolamine in older adults and glaucoma

Traps that cost points

Head CT to exclude stroke in acute vertigo→ CT misses most posterior fossa infarcts; use bedside head impulse, nystagmus and skew testing and MRI with diffusion.
Daily meclizine for BPPV→ Antivestibular drugs delay compensation; the Epley maneuver cures most cases.
Aminoglycoside ear drops with a perforated eardrum→ They are ototoxic through a perforation; use fluoroquinolone drops.
Labeling sudden one-sided hearing loss as wax or a cold→ Sudden sensorineural loss needs audiometry and steroids within days; delay lowers recovery.
Oral antibiotics alone for otitis externa→ Topical drops reach far higher concentrations; reserve oral or IV therapy for spread beyond the canal or necrotizing disease.
Irrigating the ear of a child with tympanostomy tubes→ Water passes into the middle ear; remove cerumen manually instead.