Ephedrine pharmacological effects

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 is an indirectly acting adrenomimetic amine that depends for its action on the release of norepinephrine from noradrenergic nerves. Its pharmacological effects are similar to those of ephedrine however, its CNS stimulant activity is somewhat greater. Both systolic and diastolic blood pressures are increased by oral dosing with amphetamine. The heart rate is frequently slowed reflexively. Cardiac output may remain unchanged in the low- and moderate-dose range. 

In patients with ischemic heart disease, ephedrine can cause myocardial infarction and potentially fatal dysrhythmias (31). Caution is needed in patients with any form of cardiac disease. At one time an attempt was made to use high doses of ephedrine for the early treatment of ventricular fibrillation, but its pharmacological effects rmhtated against its use, since the immediate survival rate actually fell. 

Ephedrine is essentially a sympathomimetic drug. The pharmacological effects of ephedrine resemble those of adrenaline, but various differences have been observed ... 

Comparative investigations on the stereoisomerides of ephedrine, made by Fujii (301), Pak and Read (302), Chopra, Dikshit and Pillai (303, 304, 305), Chen, Wu and Henriksen (306) and others, showed that they have similar pharmacological effects to those of ephedrine, but differ in some particular direction and intensity of action. Compared indirectly with adrenaline, in pithed cats, i-ephedrine is about three times stronger than d-ephedrine. f-Ephedrine is five times as potent as d- -ephedrine, which is seven times as potent as f- -ephedrine (307). Pak and Read, by direct comparison in anesthetized dogs, found that f-ephedrine is twice as effective as d- -ephedrine. 

Comprehensive reviews about the chemistry and pharmacology of ephedra and its use in sports and weight loss products have recently been published.The pharmacological effects of maHUANG are generally attributed to ephedrine, which include central nervous system (CNS) stimulation, peripheral vasoconstriction, elevation of blood pressure, bronchodilatation, cardiac stimulation, decrease of intestinal tone and motility, mydriasis, and tachycardia, among others (zhou). The central stimulant action of ephedrine appears to be mediated by /-adrenoceptors and not by dopamine receptors. ... 

Cardiopulmonary effects of ephedrine in halothane-anesthetized horses. Journal of Veterinary Pharmacology and Therapeutics 12 389-396 Greene S A, Thurmon J C, Tranquilli W J et al 1986 Cardiopulmonary effects of continuous intravenous infusion of guaifenesin, ketamine, and xylazine in ponies. American Journal of Veterinary Research 47 2364-2367... 

The basic pharmacological action of Ephedrine is that of a sympathomimetic. It does not contain a catechol moiety and is effective after oral administration. The drug stimulates heart rate and cardiac output and variably increases peripheral resistance as a result, ephedrine usually increases blood pressure. Stimulation of the a-adrenergic receptors of smooth muscle cells in the bladder base may increase resistance to the outflow of urine. Activation of S-adrenergic receptors in the lungs promotes bronchodilation. Ephedrine stimulates the cerebral cortex and subcortical centers to produce its effects in narcolepsy and depressive states. 

Hordenine resembles ephedrine in many of its pharmacological actions. However, on the isolated guinea pig uterus, concentrations ranging from 1 250,000 to 1 1,250 are without effect. The tonus and movements of the uterus in vivo are augmented by doses of 1,0 mg./kg., the response increasing with the dosage (217). 

Almost all analogs of ephedrine and epinephrine have been synthesized and subjected to pharmacological evaluation. Some of them are used in medicine. The list includes amphetamine or benzedrine (XX), deoxy-ephedrine (XXI), vonedrine (XXII), propadrine (XXIII), paredrine (XXIV), veritol (XXV), suprifen (XXVI), and neosynephrine (XXVII). They are advocated as vasoconstrictors in otolaryngology. The marketed form of neosynephrine is the Z-isomer. Amphetamine and deoxyephedrine are now better known for their stimulating action on the central nervous system (78, 79) and are used by persons whose duties call for long periods of alertness. The d-forms of both amines are more effective than the Z-forms in this respect. The commercial names of cZ-deoxyephedrine and cZ-amphetamine are pervitin and dexedrine, respectively. Two catechol derivatives have been recommended as substitutes for epinephrine. They are epinine (XXVIII) and corbasil (XXIX). 

The pharmacology of ephedrine was reinvestigated in Japan by Amatsu and Kubota (81), who demonstrated the adrenaline-hke effects of the alkaloid, a conclusion also reached by other oriental workers. Since the results were published in Japanese, little attention was paid to them in the Western world. 

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