This handout is for autonomic dysreflexia (sci ≥t6; remove trigger first, short-acting titratable drugs second). Your care team identified this based on: sudden severe pounding headache + flushing/sweating above the lesion ± nasal congestion in a known sci patient — classic autonomic dysreflexia until proven otherwise.
Other reasons your team may use this plan: paroxysmal sbp rise ≥20-40 mmhg above the patient's sci baseline (baseline often only 90-110 mmhg) ± reflex bradycardia — ad crisis even if absolute sbp looks "only" 150-160; spinal cord injury at or above t6 presenting with new hypertensive symptoms — anatomic substrate for ad (splanchnic outflow above lesion uncontrolled); blurred vision, apprehension, piloerection and cool pale skin below the lesion in an sci patient — sympathetic over-discharge below + parasympathetic flushing above.
Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.
| Medication | Starting dose | How | When | What it does |
|---|---|---|---|---|
| Upright positioning + loosen constrictors + trigger removal (PRIMARY therapy) | Sit fully upright, lower legs, loosen clothing/binders/leg-bag; unblock or replace catheter; disimpact bowel with topical anaesthetic; offload pressure injury | N/A | immediate, before drugs | Consortium for Spinal Cord Medicine AD guideline — positioning + trigger eradication is definitive and resolves the majority of episodes; bladder cause in ~75-85% |
| nitroglycerin | GTN 0.4 mg SL spray or 2% paste 1 inch to skin (wipe off once BP controlled) | SL/topical | repeat/titrate q3-5 min to SCI baseline | Rapid onset, easily removed (paste wiped off) for fast offset when trigger relieved — Krassioukov 2009 (PMID 19651276); ABSOLUTELY CONTRAINDICATED if PDE5 inhibitor within 24 h (sildenafil/vardenafil) or 48 h (tadalafil) |
| nifedipine (immediate-release) | 10 mg capsule bite-and-swallow | PO | may repeat once after 20-30 min | Short-acting, no nitrate interaction with PDE5i — preferred when sildenafil/tadalafil precludes GTN; bite-and-swallow (NOT sublingual) for predictable rapid absorption per AD guideline |
| captopril | 25 mg sublingual/chewed | SL/PO | once; reassess in 15-20 min | Rapid-onset short-acting alternative; avoid if hyperkalaemia or significant CKD (SCI patients have high CKD prevalence — check eGFR) |
| labetalol | 10-20 mg IV over 2 min, repeat/double q10 min (max ~300 mg) in a monitored setting | IV | titrate to SCI baseline | IV titratable for refractory/severe AD with monitoring; combined alpha-beta blockade counters the sympathetic surge — ESC/ESH 2023 hypertensive-emergency framework |
| sodium nitroprusside | 0.3-0.5 mcg/kg/min IV, titrate (arterial-line monitored ICU) | IV | continuous, titrate to SCI baseline | Ultra-short half-life ideal for the abrupt offset when trigger relieved; ICU/arterial-line only; CONTRAINDICATED with recent PDE5 inhibitor; watch cyanide accumulation if prolonged |
| prazosin | 1-2 mg PO at night (recurrence prophylaxis, NOT acute rescue) | PO | daily, for recurrent AD prevention | Alpha-1 blockade reduces frequency/severity of recurrent AD between episodes; titrate cautiously given low SCI baseline BP — Krassioukov 2009 |
| AVOID long-acting / slow-titration antihypertensives | AVOID amlodipine, long-acting nifedipine GITS, slow IV nicardipine-only strategies as the acute agent | N/A | N/A | BP can normalise abruptly the instant the trigger is relieved — long-acting agents cause profound overshoot hypotension on a low SCI baseline; this inverts the generic "gradual ≤25%/h" hypertensive-emergency paradigm |
Plan: Autonomic dysreflexia pharmacotherapy — trigger removal FIRST; short-acting titratable agents only while trigger is being relieved; nitrates contraindicated with recent PDE5 inhibitor (Consortium for Spinal Cord Medicine; 2025 ACC/AHA)
Contact your care team if any of the following happen:
Call 911 or go to the nearest emergency room right away if you have:
SCI/rehab + urology co-management: optimise bladder programme (catheter type/schedule, treat detrusor overactivity), bowel programme, skin surveillance. Provide written AD emergency protocol + wallet card; pre-procedure AD prophylaxis plan (prophylactic nifedipine or topical anaesthetic before cystoscopy/colonoscopy/urodynamics); pregnancy AD plan with MFM if applicable; educate caregivers
Guideline: Consortium for Spinal Cord Medicine — Acute Management of Autonomic Dysreflexia (PVA CPG) + 2025 ACC/AHA Hypertension + ESC/ESH 2023 hypertensive emergencies