Ephedrine Monoamine oxidase inhibitors

Synergy of unwanted pharmacological effect ginseng and its products will inhibit the central nervous system (CNS) when they are applied with luminal, chloral hydrate, or ephedrine, which can increase the release of dopamine, noradrenaline, and serotonin in the CNS thus inducing a hypertensive crisis if monoamine oxidase inhibitors (MAOIs) are given simultaneously. 

Amphetamine and cocaine also increase noradrenaline release and a number of drugs with mainly noradrenergic actions can also cause a hyperactive delirium. These include ephedrine, phenylpropanolamine, aminophylline, maprotiline and monoamine oxidase inhibitors (Hollister, 1986). 

Antidepressants monoamine oxidase inhibitors can cause hypertension when combined with certain amines, e.g. pethidine, or indirect-acting sympa-thomimetics, e.g. ephedrine. Tricyclics potentiate catecholamines and some other adrenergic drugs. 

Monoamine oxidase inhibitors can dangerously potentiate the hjrpertensive effects of ephedrine (38). 

As with other sympathomimetic agents, theoretical drug interactions with ephedra alkaloids are possible. Despite this potential, only a handful of adverse drug interactions have been reported. This is especially pertinent when considering the extensive use of both ephedra-containing supplements and ephedrine- or pseudoephedrine-containing OTC products. The most notable interaction exists between nonselective monoamine oxidase inhibitors and ephedra- or ephedrine-containing products. 

The ephedra alkaloids are all sympathomimetic amines, which means that a host of drug interactions are theoretically possible. In fact, only a handful of adverse drug interactions have been reported in the peer-reviewed literature. The most important of these involve the monoamine oxidase inhibitors (MAOI). Irreversible, nonselective MAOIs have been reported to adversely interact with indirectly acting sympathomimetic amines present in many cough and cold medicine. In controlled trials with individuals taking moclobemide, ephedrine s effects on pulse and blood pressure were potentiated, but only at higher doses than those currently provided in health supplements (137). Ephe-drine-MAOI interaction may, on occasion, be severe enough to mimic pheo-... 

Monoamine oxidase inhibitors and many pharmacological agents are synergistic, sometimes resulting in a hypertensive crisis. The agents with which the MAOIs may be synergistic include amphetamine, dextroamphetamine, methyl amphetamine, ephedrine, procaine preparations (which usually contain norepinephrine), epinephrine, methyldopa, and phenylpropanolamine (over-the-counter cold preparations). 

Martyr JW, Orlikowski CEP. Epidural anaesthesia, ephedrine and phenylephrine in a patient taking moclobemide, a new monoamine oxidase inhibitor. Anaesthesia 996) 51, 1150-2. 

The contraindications to ephedrine are angle-closure glaucoma, patients anesthetized with cyclopropane or halothane, cases in which vasopressor drugs are contraindicated (e.g., thyrotoxicosis, diabetes mellitus, hypertension during pregnancy), or treatment with monoamine oxidase (MAO) inhibitor therapy. 

Dingemanse J, Guentert T, Gieschke R, Stabl M. Modification of the cardiovascular effects of ephedrine by the reversible monoamine oxidase A-inhibitor moclobemide. J Cardiovasc Pharmacol 1996 28(6) 856—861. 

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