Acute weakness (ED workup — focal + generalized + fluctuating)

Call 911 or go to the nearest emergency room right away if you have:

• Acute focal weakness / facial droop / dysarthria within 4.5 h of last-known-well — IV alteplase / tenecteplase candidate; activate stroke pathway (Powers AHA/ASA 2019 PMID 31662037)(life-threatening)
• NIHSS ≥6 OR clinical LVO syndrome (gaze deviation, neglect, aphasia, hemiparesis) — CTA head/neck + endovascular thrombectomy ≤24 h (DEFUSE-3 / DAWN) (Powers 2019; Saver NEJM 2019)(life-threatening)
• Focal deficit fully resolved within 24 h (typically <1 h) — TIA; ABCD2 ≥4 → admit + dual antiplatelet (CHANCE/POINT); urgent vascular workup (Johnston Lancet 2007)
• Ascending symmetric weakness + areflexia + recent viral illness 1-3 wks prior — Guillain-Barré; LP (albumin-cytologic dissociation) + IVIG 0.4 g/kg/day × 5 d OR PLEX; intubate if FVC<20 (van den Berg 2014 PMID 24163275)(life-threatening)
• Fatigable weakness + ptosis / diplopia / dysphagia / dysarthria + falling FVC — myasthenic crisis; IVIG or PLEX + pyridostigmine + steroids; intubate if FVC<20 (Sanders MGFA 2016 PMID 27358333)(life-threatening)
• Bilateral leg weakness + sensory level + saddle anesthesia + urinary retention/incontinence — STAT MRI + dexamethasone 10 mg IV + neurosurgery (Greenberg AAN PMID 12236201; Greenhalgh Spine 2015)(life-threatening)
• Subacute bilateral weakness + sensory level + bladder dysfunction over hours-days — transverse myelitis; MRI + LP + IV methylprednisolone 1 g × 3-5 d
• Descending symmetric weakness + cranial nerves (diplopia, dysphagia, dysarthria, dysphonia) + dilated/fixed pupils + autonomic + canned food/wound — botulism; HBAT from CDC + ICU (Sobel CDC PMID 33956777)(life-threatening)
• Recurrent episodic generalized weakness sparing respirations + K extremes (<2.5 hypoK or >6.5 hyperK) — channelopathy (hypokalemic, hyperkalemic, thyrotoxic); replete K + treat trigger
• Myalgia + weakness + dark urine + CK >5000 (often >10,000) + heme-positive UA without RBCs → myoglobinuria → AKI risk; aggressive LR + electrolyte correction (Bosch NEJM 2009 PMID 19571284)
• Na <120 with weakness / AMS / seizure — severe symptomatic hyponatremia; 3% saline 100 mL IV bolus × 1-3 (max 4-6 mEq/L correction in 24 h) → syndrome.hyponatremia.core.v1(life-threatening)
• Focal deficit with glucose <70 mg/dL — #1 stroke mimic; D50 25 g IV bolus + D10 infusion; reassess neuro exam after glucose ≥100