Ephedrine

Ephedrine is a natural phenylethylamine alkaloid that occurs as the main alkaloid in ephedra species(e.g. Ephedra sinica, Chinese seaweed - also known as "mahuang") and Catha edulis. The substance forms a crystalline white powder with a bitter taste. Ephedrine is soluble in 4 parts water and ethanol.

Ephedrine releases norepinephrine and thus leads to an increase in adrenergic transmission. Since it has no hydroxy groups on the phenyl ring, it can pass the blood-brain barrier (although not as efficiently as amphetamine or methamphetamine).

In isolated or synthetically produced form, ephedrine - as well as the diastereomers D-pseudoephedrine and D-norpseudoephedrine - is used in bronchial asthma and rhinitis due to its sympathomimetic effect. Ephedrine can have a circulatory stimulating, drive and performance-enhancing, appetite-inhibiting, but also relaxing and, in some people, slightly sexually stimulating effect. It increases the urge to move, attention and the need to communicate.

The usual dose is 25-50 mg/day p.o.

In case of overdose the side effects are many: restlessness, anxiety, nausea, insomnia, tremor, pulse racing, sweating, difficulty breathing, confusion, hallucinations, delirium, headache, rarely: cramps.

Until 2001 ephedrine preparations were freely available in German pharmacies. Ephedrine was misused as an appetite suppressant, party drug. Ephedra herba is also available only on prescription in German pharmacies. Because of its appetite-suppressant and subjectively performance-enhancing effect, ephedrine is often used as a (prohibited) doping agent, often in combination with caffeine and acetylsalicylic acid.

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