Most over-the-counter medicine for weight-loss consists of appetite suppressants. They work by "tricking" the body into thinking that it is not hungry. This can be effective; however, long-term use can lead to addiction and may cause health problems. In addition, weight loss only occurs while you are taking the medicine, unless other behavioral changes such as improved diet and increased exercise are made.
Below are some commonly used over-the-counter weight loss drugs and appetite suppressants. Be sure to talk to your doctor before taking any of these over-the-counter drugs, as some could be a waste of money, or worse, dangerous.
- Ephedrine (ma-huang). Ephedrine is a common ingredient in herbal dietary supplements used for weight loss. Ephedrine is used in asthma medicine, as well as to make methamphetamine, more commonly known as speed. In fact, there's only a slight difference chemically between methamphetamine and ephedrine. Ephedrine can slightly suppress your appetite, but no studies have shown it to be effective in weight loss. Ephedrine can also be dangerous. It can cause high blood pressure, irregular heartbeat, insomnia, nervousness, tremors, seizures, heart attacks, strokes and even death. Ephedrine can also interact with many prescription and over-the-counter medications. In February 2004, the FDA officially banned the sale of ephedrine in any dietary supplement in the U.S. due to the risk of illness or injury.
- St. John's wort. This herbal product is primarily used as an antidepressant. Few studies have evaluated its effectiveness for promoting weight loss. St. John's wort is one of the primary ingredients in herbal phen-fen. If you are taking St. John's wort, you should avoid tyramine containing foods (for example, aged meats, cheese, wines, etc.). You should also avoid medications such as Prozac, Zoloft, Paxil, Effexor, Remeron, Serzone, Buspar, and dextromethorphan (contained in various cold remedies). The use of St. John's wort for weight loss is potentially very dangerous.
- 5-hydroxytryptophan (5-HTP). Found in some over-the-counter weight loss formulas, this extract from a West African plant seed contains a contaminant linked to a rare and potentially deadly blood disorder. It has not been proven to effectively promote weight loss.
- Chitosan (KITE-o-san). This dietary supplement is made from chitin, a starch found in the skeleton of shrimp, crab and other shellfish. Chitosan cannot be digested therefore it passes through your intestinal tract unabsorbed without adding any calories. The chemical nature of Chitosan makes it bind with fatty foods, removing some of the fat from your body as it passes though rather than allowing it to be absorbed. One study, however, found no more weight loss from Chitosan than from a placebo (sugar pill).
- Pyruvate. Pyruvate is formed in the body during digestion of carbohydrates and protein from food. It may have a slight effect in helping you shed pounds, according to some studies. Found in the form of pyruvic acid, pyruvate can be found in various foods including red apples, cheese and red wine. Pyruvate appears to be safe, but claims of boosting metabolism, decreasing appetite and aiding in weight loss need further study.
- Aloe. Most often used as a topical product for wound healing, oral forms of aloe are added to herbal weight-loss products. Oral aloe produces a strong cathartic response (producing bowel movements) and many aloe weight-loss products are marketed as "internal cleansers." However, aloe or aloe containing products should not be ingested orally. Use of this agent orally has lead to side effects such as abdominal cramping, diarrhea, and problems with the body's mineral balance. In addition, it can interact with medications such as Lanoxin (digoxin), a medicine used to treat heart failure. The use of aloe has not been proven to keep weight off.
- Cascara. Cascara is a common ingredient used in weight loss products. One of the few herbs approved as an over-the-counter drug by the FDA, it is a strong stimulant laxative. Misuse of this herb has caused problems with the body's minerals (such as potassium, sodium). It should not be taken if you are pregnant or breastfeeding. Cascara may interact with medications such as Lanoxin and diuretics (water pills, used to treat hypertension and other health problems).
- Dandelion. Dandelion is a natural diuretic. It may produce significant weight loss by decreasing body water. However, it can cause allergic reactions and may even cause cancer.
- Glucomannan. Made from the root of Amorphophallus Konjac, glucomannan is said to contribute to weight loss by delaying the absorption of glucose from the intestines. Small limited studies have shown glucomannan to be effective in decreasing body weight. This effect is believed to be due to a "feeling of fullness" which may be due to the swelling of the glucomannan in the gut once it has been exposed to liquids. However, esophageal obstruction has been reported in several people taking glucomannan. Glucomannan and glucomannan-containing products have been banned in several countries due to the high incidence of gastrointestinal obstruction. Glucomannan should not be used by people with diabetes or in people with a previous history of gastrointestinal obstruction.
- Guarana. Made from the seeds of a plant native to Brazil, guarana speeds up the brain's activity and is used to promote weight loss due to its stimulant and diuretic effect. Guarana contains 2.5% to 5% caffeine and may cause high blood pressure. Some of the extracts have been known to cause prolonged bleeding and interact with blood thinner medication such as Coumadin. Many advertisements state guarana is free from side effects; however this statement is not true. Side effects from guarana may include: nausea, dizziness and anxiousness.
- Yerba Mate. Also known as Paraguay tea, yerba mate is a strong brain stimulant (the doses typically used mimic that of 100 to 200 mg of caffeine). The principle side effects reported are excessive stimulation and high blood pressure. It has not been proven to promote weight loss. Some case reports of poisoning (leading to hospitalization) with this agent have been reported and excessive use has been linked to cancer of the esophagus.
- Guar Gum. Also known as guar, guar flour, and jaguar gum, guar gum is a dietary fiber obtained from the Indian cluster bean. Guar gum has been used extensively as a thickening agent for foods and medications. It has been noted to decrease appetite by providing a "feeling of fullness." However, like glucomannan, guar gum may cause obstruction of the esophagus. The water-retaining capacity of the gum permits it to swell to 10 to 20 fold and has led to gastrointestinal obstructions. Guar gum has also been known to cause significant fluctuations in blood sugar levels, thus people with diabetes should not use these preparations.
- Herbal Diuretics. There are many varieties of herbal diuretics that are commonly found in over-the-counter weight loss products as well as herbal weight loss preparations. Most of the diuretics used in over-the-counter treatments are derived from caffeine. You should avoid preparations that contain juniper seeds (capable of causing renal damage), equistine (neurotoxic, can cause brain damage) and horse tail or shave grass (includes several toxic compounds that can cause convulsions or hyperactivity). Most of the herbal diuretics are not toxic but have been known to interact with medications (for example, lithium (Lithobid, Eskalith), Lanoxin, or conventional diuretics such as Lasix or Esidrex). Most of the herbal diuretics do not provide enough water loss to be considered effective in losing weight.
Common Sense Advice for Taking Herbal Medicines
- If you become ill while taking an herbal remedy, see a doctor or consult with a health care professional.
- Do not take herbs if pregnant or attempting to become pregnant.
- Do not take herbs if you are nursing.
- Do not give herbs to a baby.
- Do not take large quantities of any one herbal preparation.
- Do not take any herb on a daily basis.
- Buy only preparations in which the plants are listed on the packet (Note: There is no guarantee attached to any product.)
- Do not take herbal remedies if you are taking medicine for a chronic condition (for example, high blood pressure or depression). If you are unsure consult with your doctor prior to taking any herbal preparation.
- Do not take herbal remedies without first talking to your doctor.
- Always advise your doctor of any herbal remedy or alternative medicine you are taking.
Keep in mind that herbal preparations will not provide permanent weight loss and there are multiple ingredients in herbal weight loss preparations, some of which have serious side effects and can lead to dangerous toxicities. The use of herbal remedies to lose weight is not recommended by the medical community due to the high risk of toxicities and lack of clinical effectiveness.
Reviewed by the Department of Nutrition Therapy at The Cleveland Clinic.
Edited by Charlotte Grayson, MD, WebMD, August 2004.
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