Hypertension amphetamines causing

The continuous use of amphetamine causes tolerance, requiring higher doses, and hence there exists a high potential for its abuse. Amphetamine should not be used with a monoamine oxidase A inhibitor such as tranylcypromine, because the chance of inducing hypertension becomes magnified. 

Until recently, d-fenfiuramine was used to control appetite, in preference to d-amphetamine, because it has a lower affinity for the catecholamine transporter and so its uptake into noradrenergic and dopaminergic neurons is much less than that of amphetamine. This is thought to explain why, at anorectic doses, this compound lacks the psychotropic effects and dependence-liability that are real problems with if-amphetamine. Unfortunately, despite this therapeutic advantage, this compound has had to be withdrawn from the clinic because of worries that it might cause primary pulmonary hypertension, valvular heart disease and even long-term neuropathy. 

Predictable interactions occur between the MAOIs and any amine precursors, or directly or indirectly acting sympathomimetic amines (e.g. the amphetamines, phenylephrine and tyramine). Such interactions can cause pronounced hypertension and, in extreme cases, stroke. 

Amphetamines and anorexic agents These drugs have potential for causing dependence, hypertension, angina, and myocardial infarction. High... 

Desmethylselegiline is also an irreversible inhibitor of monoamine oxidase B in humans. There is evidence that the 1-stereoisomers of 1-amphetamine and 1-methamphetamine may have some qualitatively different actions from their d-isomer counterparts, which might result in beneficial clinical effects and could complement any beneficial clinical actions of selegiline itself. Food has no effect on the pharmacokinetics of desmethylselegiline, methamphetamine, and amphetamine. At a dose of 10 mg per day, selegiline is devoid of the cheese effect that is, it does not cause hypertension when taken with tyramine-containing foods such as cheese. 

Among the materials which may be dangerous in combination with MAO inhibitors are sedatives, tranquilizers, antihistamines, narcotics, and alcohol -- any of which can cause hypotensive crisis (severe blood pressure drop) and amphetamines (even diet pills), mescaline, asarone, nutmeg (active doses), macromerine, ephedrine oils of dill, parsely or wild fennel beer, wine, cocoa, aged cheeses, and other tyrosine-containing foods (tyrosine is converted into tyramine by bacteria in the bowel) -- any of which can cause hypotensive or hypertensive (severe blood pressure rise) crises. 

Correct choice = B. Amphetamines should not be used in patients receiving MAO inhibitors, since amphetamine itself weakly inhibits MAO. Chlorpromazine relieves the CNS symptoms and the hypertension because of its a-blocking effects. The euphoria caused by amphetamine lasts 4 to 6 hours, or 4 to 8 times longer than the effects of cocaine. 

MAOIs slow absorption of amphetamines and thus potentiate their actions, which can cause headache, hypertension, and rarely hypertensive crisis and malignant hyperthermia, sometimes with fatal results... 

Sympathomimetic syndromes include tachycardia, hypertension, hyperthermia, sweating, mydriasis, hyperreflexia, agitation, delusions, paranoia, seizures and cardiac arrhythmias. These are commonly caused by amphetamine and its derivatives, cocaine, proprietary decongestants, e.g. ephedrine, and theophylline (in the latter case, excluding psychiatric effects). 

Anorectic drugs, which are structurally related to the amphetamines, act mainly on the satiety centre in the hypothalamus and also increase general physical activity (1). All of them, except fenfluramine, stimulate the central nervous system and can cause restlessness, nervousness, irritabihty, and insomnia. Adverse effects also occur through sympathetic stimulation and gastrointestinal irritation. Drug interactions can occur with monoamine oxidase inhibitors. Dexamfetamine, phenmetrazine, and benzfetamine can cause dependence. Some of them have been associated with cardiac valvulopathy and primary pulmonary hypertension (2). 

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