Generally speaking, drugs are of limited value in the treatment of obesity and should be used with great care (preferably under medical supervision) because of the possibility of dependence and abuse. The most commonly used are the `anorexigenic' drugs which work by suppressing appetite. However, their effect is only temporary and they do nothing to encourage changes in the eating habits which caused the problem in the first place. Also, an ever-increasing dosage is needed for sustained weight loss.
Side effects of these drugs include insomnia, excitability, dryness of the mouth, gastro-intestinal disturbances and addiction. Anorectics increase short-term weight loss but interestingly, follow-up indicates that patients treated with drugs lose less weight in the long term.
There are many other drugs which have received attention in the treatment of obesity. For example:
- thyroid hormone, which increases energy use. Unfortunately, both fat and protein losses occur when this drug is used. Also, the results of thyroid medication seem to be no better than those achieved with a balanced diet alone - and negative side effects involving the heart have been reported.
- growth hormone, which decreases fat stores without causing protein losses. This hormone, however, is in short supply and is not generally used in the treatment of obesity.
- human chorionic gonadotrophin (HCG), which is injected and used along with a very low calorie (500 cal/2 100 kJ) diet. It is claimed that this hormone melts away fat and reduces hunger. However, no scientific proof for these claims has been found.
- drugs which interfere with the absorption of carbohydrates and fats. This implies that one can eat as much as you like without getting fat, because all the energy is not absorbed. More research is needed on these drugs to evaluate their long-term efficacy in humans.
- bulking agents, which are intended to fill the stomach with indigestible material in the hope that the resulting feeling of fullness will make the obese person eat less. (Research indicates that this method is not very effective and that it causes flatulence.)
Perhaps the most important point to remember regarding the use of drugs in combatting overweight is that, while they may aid the slimming process, they do not solve the underlying problem and will therefore never be effective as a sole treatment for obesity.
The surgeon's knife
Surgical treatment of obesity is usually the last resort and is generally only used on the excessively obese person when all other method have failed. Surgical procedures used include small bowel bypass and/ or stapling of the stomach, biliopancreatic bypass and jaw wiring. The chances of success are small unless the patient is highly motivated and prepared to follow a very strict diet. Also, these techniques involve considerable risk and could result in the development of other health problems as side effects.
