DOES IT WORK?:Remedies may be natural but they're not always safe, writes Dónal O'Mathúna
MANY PEOPLE turn to herbal remedies in the belief that if they are natural, they must be safe. Strychnine, carbon monoxide and many other natural substances show this is not the case.
Ephedra has led to many reports of adverse effects and some deaths.
The US drug regulatory agency, the FDA, banned its sale in 2004, though only after years of attempting to restrict its sale. Even while evidence mounted of ephedra's danger, it remained one of the most popular herbal remedies.
Ephedra is also known by its Chinese name, ma huang, as "herbal ecstasy" because of its stimulant effects, and as "herbal fen-phen", after a weight-loss drug combination taken off the market several years ago.
Ephedra products are made from several ephedra species which contain different mixtures of compounds called alkaloids. Ephedrine is the most common alkaloid, which in purified form is used to treat asthma, as a nasal decongestant, and to increase blood pressure and heart rate.
A small number of other ephedra alkaloids have been used as conventional drugs.
Evidence from studies
Herbal ephedra contains ephedrine and does increase blood pressure and heart rate. However, herbal products vary widely in how much ephedrine and other alkaloids they contain. This may be why they have led to many side effects.
Ephedra is most commonly recommended to help people lose weight or to improve athletic performance. During the controversy in the US over ephedra regulation, an independent review of ephedra research was commissioned.
For use in losing weight, one study of ephedra alone and four of ephedra containing multiherb mixtures found that, on average, people lost one kilogram per month more taking ephedra compared to a placebo.
No studies examined ephedra to improve sports performance. Purified ephedrine was examined in some trials. Alone, it gave no improvements, though in combination with caffeine it showed some performance enhancement.
All these studies reported significant increases in heart rate and blood pressure, but whether this led to better performances in competition was not examined.
Problematic aspects
In contrast with the small benefits found in studies, many adverse effects were found. When ephedra sales made up less than 1 per cent of the US market, it led to 64 per cent of all herbal adverse event reports made to poison control centres.
In many studies, those taking ephedra or ephedrine had three to four times more side effects. Common reactions included high blood pressure, increased heart rate, heart palpitations, anxiety, restlessness, agitation, and headache.
About one-third of those given higher doses had nausea and vomiting. Ephedra was also linked with very serious side effects, such as heart attack, stroke, psychosis and sudden death.
It has been suspected to play a role in the sudden deaths of some highly competitive athletes.
While supporters of ephedra claim serious side effects occur only when people use very high doses for long periods, this has not always been the case. Some people appear to be very sensitive to the drug. In addition, ephedra is likely to interfere with other drugs being taken for heart conditions or mental health.
Recommendations
Use of ephedra to enhance sports performance is not supported by research. The herb does stimulate the heart, but there is no evidence this improves performance.
The herb is also banned by the International Olympic Committee and other sports organisations.
While ephedra has been found to help a little when taken for weight loss, the risks far outweigh the limited benefit.
Given these risks and lack of effectiveness, use of ephedra cannot be recommended for anyone.
• Dónal O'Mathúnahas a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, Dublin City University. He is author of Alternative Medicine: The Christian Handbook(Zondervan, 2007).