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Is a common pain reliever safe during pregnancy? Morton , Mary L. Hardy , Margaret A. Use Adobe Acrobat Reader version 10 or higher for the best experience. Products that contain the herb ephedra have been promoted and used in the United States since the s to increase weight loss and enhance athletic performance.
Yet despite manufacturers' claims, little research has been done to assess whether the products are safe, and the research studies that have been done have been too small to allow any firm conclusions to be drawn. The questionable effectiveness of these products might not have raised public concern, had the U.
Food and Drug Administration FDA and major manufacturers of ephedracontaining products not become the targets of growing numbers of consumer complaints in the late s.
Reports of adverse events, including serious side effects and even deaths, many in apparently healthy young people, began increasing during this time. Prominent among the victims have been several college and professional athletes.
Thus, in recent years, several major consumer health groups have called on the FDA to ban sales of ephedra-containing products. Under DSHEA, dietary supplements are generally "presumed safe"; thus, manufacturers are required only to notify the FDA of their intent to market new products but are not required to establish the safety or effectiveness of their products.
Once a dietary supplement is on the market, the FDA can restrict its use or ban sales of the product only if it can demonstrate convincingly that the product is unsafe. As complaints continued to mount, the U. The SCEPC is one of 13 federally sponsored evidence-based practice centers nationwide that specializes in seeking answers to important health care questions through assessing and synthesizing the evidence from large numbers of research studies.
Statistically combining the findings of many similar studies increases researchers' confidence that small apparent differences in the effects of two treatments are in fact real. We were asked to review all studies of ephedra-containing dietary supplements conducted to date, to assess whether the substance actually lives up to manufacturers' claims and whether the supplements are safe for the general population, or whether they are in fact responsible for the adverse effects that have been attributed to them.
The herb ephedra, also known as ma huang, is a small, twiggy shrub native to Asia, where it has a long history of medicinal use, as documented in ancient medical treatises from India and China. Traditional Chinese and Indian medicine uses the branches of the herb to treat colds and wheezing and as a diuretic.
Modern European practitioners of herbal medicine use ephedra only to treat symptoms of respiratory diseases such as bronchial asthma. In the United States, the active components of ephedra, known as the ephedrine alkaloids ephedrine; pseudoephedrine; norephedrine, also known as phenylpropanolamine; and norpseudoephedrine are commonly found in over-the-counter cold and allergy medications. The ephedrine alkaloids are stimulants similar to, but much weaker than, amphetamines that can increase heart rate and blood pressure and relax bronchial tissue, easing shortness of breath.
At low doses, they are reputed to decrease appetite, increase alertness and productivity, improve mood, and decrease fatigue; at higher doses, they may promote anxiety, restlessness, and insomnia. The use of ephedra to promote weight loss and enhance athletic performance began to gain popularity in the United States in the early s.
The increase in popularity of herbal products and over-the-counter medications that seem to promote weight loss is probably attributable to a combination of factors, including the recent precipitous rise in overweight and obesity rates, news stories suggesting that prescription diet drugs may be dangerous, the reluctance of many overweight people to talk with their doctors about weight control, and the growing belief on the part of many people that natural substances such as herbs and those perceived as natural are safer than mainstream medicines.
People have used dietary supplements to enhance athletic performance for many years. Use of dietary supplements and over-the-counter medications containing stimulants like ephedrine to enhance athletic performance increased throughout the latter part of the 20th century, perhaps in part because of the bans imposed on use of amphetamines and because of the accelerating intensity of competitive sports.
Our assessment of the evidence was guided by a distinguished panel of technical experts, both basic scientists and clinicians. This group included cardiologists, exercise physiologists, pharmacologists, and toxicologists, as well as specialists in obesity, nutrition, and the science of pharmacognosy.
The technical expert panel recommended that we also review studies of over-the-counter medications that contain the chemical ephedrine, presumed to be the primary active ingredient of ephedra ephedrine-containing products are regulated as pharmaceuticals, not as dietary supplements.
In addition, many ephedracontaining supplements also include herbs that contain caffeine, and products that contain ephedrine often include caffeine. Because caffeine is believed to have effects that are similar to ephedrine, such combinations could potentially be more powerful than either substance alone. Thus, we were also asked to review the evidence for the effectiveness and safety of supplements that combine ephedra and caffeine as well as ephedrine and caffeine-containing products.
Many studies examining the weight loss effects of ephedrine have combined this ingredient with caffeine. The combination of ephedrine and caffeine appears to exert greater effects on your body than either ingredient alone 12 , For example, ephedrine plus caffeine increases metabolic rate more than ephedrine alone Some research has even reported that caffeine and ephedrine individually had no effects on weight loss, while the combination of the two did produce weight loss Over 12 weeks, ingesting a combination of ephedra and caffeine 3 times per day led to a reduction of 7.
Another 6-month study in overweight and obese people compared a supplement containing ephedrine and caffeine to a placebo during a weight loss program The group taking ephedrine lost 9.
The ephedrine group also decreased body weight and LDL bad cholesterol more than the placebo group. Overall, the available evidence indicates that ephedrine-containing products — particularly when paired with caffeine — may increase weight and fat loss.
Ephedrine plus caffeine may increase metabolic rate and fat loss more than either ingredient alone. Studies show the combination of ephedrine and caffeine produces greater weight and fat loss than a placebo.
Doses of ephedrine used in research vary, with intakes of less than 20 mg per day considered low, 40—90 mg daily considered moderate, and doses of — mg per day considered high. Although some positive effects on metabolism and body weight have been seen across a variety of doses, many have questioned the safety of ephedrine.
Individual studies have shown mixed results regarding the safety and side effects of this substance across a variety of doses.
Some have reported no significant side effects, while others indicate a variety of side effects that even caused participants to withdraw from the studies 10 , 17 , In-depth reports have combined the results of multiple studies to better understand concerns associated with ephedrine consumption. One analysis of 52 different clinical trials found no serious adverse events such as death or heart attack in studies on ephedrine — with or without caffeine Yet, the same analysis found these products were associated with a two- to threefold increased risk of nausea , vomiting, heart palpitations, and psychiatric problems.
Additionally, when individual cases were examined, several deaths, heart attacks, and psychiatric episodes were potentially linked to ephedra Based on the evidence, potential safety concerns were significant enough to prompt legal action in the United States and elsewhere 1.
While some individual studies did not demonstrate serious side effects of ephedra or ephedrine consumption, mild to highly concerning side effects became apparent upon examination of all available research. While the ephedra herb and products like ma huang tea are available for purchase, dietary supplements containing ephedrine alkaloids are not.
Some ephedrine-containing medications are still available over the counter, though regulations on the purchase of these products can vary by state. For this reason, some dietary supplement manufacturers will market weight loss products that contain other compounds found in ephedra, but not ephedrine alkaloids. These products may not have the safety concerns observed for products containing ephedrine — but they may also be less effective.
While some countries outside of the United States have also banned ephedrine-containing products, the specific regulations vary. Dietary supplements containing ephedrine alkaloids were banned by the FDA in
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