Adult: Initially, 15-100 mg in 500 mL of NaCl 0.9% or dextrose 5% inj via infusion, adjusting the dose at least after 10 min to maintain BP. Severe shock: Initially, 0.5-5 mg via direct inj, followed by infusion of 15-100 mg in 500 mL of diluent.
Symptoms: Severe HTN, headache, constricting chest sensation, nausea, vomiting, euphoria, diaphoresis, pulmonary oedema, tachycardia, bradycardia, sinus arrhythmia, atrial/ventricular arrhythmia, MI, cardiac arrest, convulsion. Management: Employ gastric lavage or induce emesis if the drug is ingested. Local ice packs may delay absorption if drug is administered via IM/SC inj. α-adrenergic blockers may be useful against HTN and arrhythmia. Parenteral diazepam may be given for convulsion.
Increased action w/ MAOI and TCA. Decreased pressor effect w/ α-adrenergic blockers. May cause ectopic arrhythmia w/ digitalis. Potentially Fatal: Halogenated hydrocarbon anaesth, particularly cyclopropane and halothane, may increase the sensitivity of myocardium to the effects catecholamines.
Description: Metaraminol is a potent sympathomimetic amine that increases both systolic and diastolic BP. It has direct actions on α- and β-adrenergic receptors causing peripheral vasoconstriction and positive inotropic effects. It also displaces norepinephrine from adrenergic stores and competitively inhibits its uptake. The overall effect is to increase cardiac output, peripheral resistance, and BP. Onset: 1-2 min (IV); approx 10 min (IM); 5-20 min (SC). Duration: Approx 20 min (IV); approx. 1 hr (IM).
C01CA09 - metaraminol ; Belongs to the class of adrenergic and dopaminergic cardiac stimulants excluding glycosides. Used in the treatment of hypotension.
Buckingham R (ed). Metaraminol Tartrate. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 07/07/2016.Joint Formulary Committee. Metaraminol. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 07/07/2016.Metaraminol. Gold Standard Drug Database in ClinicalKey [online]. Elsevier Inc. https://www.clinicalkey.com/. Accessed 07/07/2016.