Sympathomimetic Vasopressor (Alpha-Agonist) Pregnancy: No well-controlled studies in pregnant women; use during pregnancy only if the potential benefit to the mother justifies the potential risk to the fetus. It is not known whether metaraminol is secreted in human milk - exercise caution if breastfeeding.

Metaraminol

Brand names: Aramine

Metaraminol is a sympathomimetic vasopressor used to treat acute hypotension, particularly that arising during anaesthesia.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 0.5 to 5 mg (1 to 10 ml) by direct intravenous injection in grave emergencies; one direct IV injection should usually not exceed 1 mg

Route: Intravenous (direct IV injection)

Frequency: Bolus doses at the minimal effective dose, repeated as needed under comprehensive haemodynamic monitoring; may be followed by an IV infusion

Max: Maximum cumulative dose after repeated direct IV injections is 5 mg

Direct IV injection may be followed by an infusion of 15-100 mg in 500 ml of infusion fluid using a formulation suitable for infusion. The 0.5 mg/ml solution for injection in pre-filled syringe is NOT suitable for IV infusion or for syringe-pump drivers and is supplied ready to use for direct IV injection only (do not dilute). Not for use in children under 12 years of age. Geriatric patients may be more sensitive to sympathomimetics - use caution.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Should not be used concurrently with cyclopropane or halothane anaesthesia unless clinical circumstances demand it
Hypersensitivity to metaraminol or any excipient
Insufficient data - not recommended in children under 12 years of age

Side effects

Hypertension from excessive therapeutic effect (very common), quickly reversible by reducing the infusion rate
Headache (very common)
Palpitations, sinus or ventricular tachycardia, bradycardia and other arrhythmias
Nausea and vomiting
Injection-site abscess formation, tissue necrosis and sloughing

Interactions

Cyclopropane or halothane anaesthesia - avoid concurrent use unless clinically essential (from section 4.3; section 4.5 interactions text truncated in the fetched source and should be re-checked)

Clinical monograph

How it works

It acts predominantly as an alpha-1 adrenoceptor agonist causing vasoconstriction, and also has an indirect action through release of noradrenaline from sympathetic nerve terminals.

Prescribing in practice

It can cause severe hypertension and reflex bradycardia, so it should be titrated carefully with close blood pressure monitoring.
Extravasation can cause tissue ischaemia and necrosis; ideally administer through a secure, well-running cannula or central line.
Use with caution in patients on monoamine oxidase inhibitors or with significant cardiovascular disease.

Monitoring

Monitor blood pressure and heart rate frequently, and inspect the infusion site for signs of extravasation.

Counselling the patient

This medicine is given by the clinical team to support blood pressure and is monitored closely.
Report any pain, burning, or swelling at the drip site immediately.

Evidence & guidelines

Use reflects established perioperative practice for managing hypotension; consult current prescribing references and the SPC.

Reference: AAGBI Guidelines; RCoA Regional Anaesthesia Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Pathways