Ephedrine is a medicine that raises blood pressure and pulse. It is mainly used in childbirth anaesthesia to correct blood pressure drops, and in emergency situations with very low blood pressure.
Also known as: Efedrina sulfato
Metoprolol may block the beta-2 vasodilating component of ephedrine, favouring excessive hypertensive response and reflex bradycardia.
Ephedrine is a mixed (α and β) sympathomimetic; β1-selective blockade leaves α vasoconstriction unbalanced by β2 (ephedrine labels: hypertension with beta-blockers).
Frequent invasive/non-invasive blood pressure, heart rate.
Sudden hypertension, headache, bradycardia, angina.
For anaesthetic hypotension in beta-blocked patients, use ephedrine in smaller doses with continuous monitoring; consider phenylephrine as an alternative with caution.
DailyMed — Ephedrine Sulfate Tablet label [CVS Pharmacy], Warnings (hypertension, adrenergic interactions): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=e338deef-efad-1d82-e053-2995a90a1bf9
Ephedrine (indirect sympathomimetic) plus clonidine (central α2 agonist) can produce unpredictable pressor and sedative responses.
Clonidine reduces central sympathetic tone and noradrenaline release; ephedrine depends on that release — the pressor effect of ephedrine may be blunted, and clonidine withdrawal causes rebound hypertension.
Peri-operative blood pressure, sedation, heart rate.
Rebound hypertension, headache, agitation, tachycardia.
Never stop clonidine abruptly (rebound); peri-operatively continue clonidine and monitor blood pressure; titrate vasopressors with monitoring.
DailyMed — Ephedrine Sulfate Tablet label (adrenergics): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=e338deef-efad-1d82-e053-2995a90a1bf9; Clonidine HCl Tablet label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=d90b2ca4-7753-4012-a1b2-fb92bdf0ebb6
Caffeine adds CNS and cardiac stimulation to ephedrine — anxiety, palpitations and tachycardia; this addition is well known from classic cold remedies.
Avoid coffee, strong tea, energy drinks and chocolate during use.
Prontuário Terapêutico INFARMED, 5.2.3 (cold remedies with vasoconstrictors + caffeine — serious safety problems, l. 10215).
Ephedrine is vasoconstrictive and chronotropic — contraindicated in uncontrolled hypertension and coronary disease.
Measure blood pressure before each dose; avoid in pre-eclampsia.
Site monograph (ephedrine — caution in hypertension, coronary disease, phaeochromocytoma).
Ephedrine releases catecholamines — can trigger a fatal hypertensive crisis in phaeochromocytoma.
Contraindicated in any case of phaeochromocytoma.
Site monograph (ephedrine — phaeochromocytoma); BD vocabulary (phaeochromocytoma).
Ephedrine is the historical reference vasopressor for epidural-related hypotension in labour (minimal placental transfer). Annex 1 does not list it in isolation, but sympathomimetics in general (pseudoephedrine, l. 41446) have been associated with gastroschisis with 1st-trimester exposure — precaution. At usual obstetric doses (5–10 mg IV) experience is long and favourable; high doses are associated with fetal acidosis and tachycardia.
Use at usual obstetric doses for spinal anaesthesia hypotension; prefer phenylephrine when available (less fetal acidosis); avoid chronic/oral use.
Passes into milk and may cause infant irritability and insomnia at high or repeated doses; a single obstetric dose is compatible.
Prontuário Terapêutico INFARMED — Annex 1: Pseudoephedrine/sympathomimetics (l. 41446); Annex 2: "Ephedrine" (l. 42529). OMS/LNME — ephedrine as obstetric vasopressor.
Clinical and educational support tool. The information does not replace a medical prescription or the opinion of a qualified healthcare professional.
↑ blood pressure, ↑ heart rate, bronchodilation and mydriasis; IV onset in 1–2 min, duration 30–60 min.
Direct α1/β1/β2 action and indirect (noradrenaline release from the axon via exchange mechanism); tachyphylaxis through noradrenaline depletion.
Oral: good absorption; IV/IM: immediate/5–15 min action; crosses the blood-brain barrier (CNS effect).
Partially hepatically metabolised (N-demethylation); 70–90% excreted unchanged in urine (slower in alkaline urine).
~ 3–5 h (oral; longer with alkaline urine).
Medicines from the same therapeutic group (ATC classification) or the same pharmacological class.
