FDA-Approved Weight Loss Drugs

While many supplements and weight loss aids claim to be able to help people lose weight, the Food and Drug Administration is strict in its support of such drugs. Very few FDA-approved weight loss drugs are on the market, most of which require a prescription. Because of the inherent risks associated with taking any of these drugs, it's important that you always consult with a doctor before taking one.

Alli

Alli is the first over-the-counter weight loss pill approved by the FDA. Basically a reduced-strength version of Xenical, it is meant only for people over 18 and must be used along with a low-fat diet. Alli prevents the enzyme lipase from breaking down fat, so the body can't absorb whatever it is consumed through diet. However, because fat is not longer absorbed, it passes through the intestines in raw form and can result in oily spotting, diarrhea, cramps and gas. Because of the bothersome side effects, Alli naturally encourages users to consume less fat, which in turns leads to weight loss.

Xenical

Xenical (orlistat) is a prescription drug that acts in the same way than the milder Alli, except that while Alli contains 60 milligrams of the fat-blocking component, Xenical contains 120 milligrams. This difference is enough to easily cause serious digestive problems, so Xenical should be used only by people who are seriously overweight and only under the supervision of a doctor. People taking Xenical will need to also take a multivitamin, as lack of fat absorption can lead to some essentials nutrients being lost from the body at an accelerated rate. People on medication for diabetes, heart disease or cholesterol may not be good candidates for this drug, as it can reduce the efficacy of the medication.

Meridia

Meridia (sibutramine) is a prescription drug that helps people lose weight by affecting the satiety center of the brain, bettering mood and decreasing appetite. Meridia is only meant to be used short-term because it causes an increase in blood pressure and can lead to lasting problems if abused. It also leads to restlessness, dizziness, tremors, insomnia and allergic reactions. Because Meridia reduces appetite, most patients on it do not have to give up any food groups or drastically reduce their fat intake. Meridia should be used alongside a healthy diet, but this is more due to a long-term health concern than to increase the efficacy of the drug.

Adipex-P

Adipex-P (phentermine) causes a "high" in the body similar to the one produced by drugs like speed and anphetamines. This increases metabolism and leads to rapid weight loss. Adipex-P is recommended for obese people with a serious health condition such as diabetes or heart disease and who need to lose weight as quickly as possible to better their health. Adipex-P is only effective for a few weeks, after which weight loss stops. This drug can be addictive and lead to serious side effects such as heart palpitations, tremors, hallucinations (or sudden depression), restlessness, impotence and high blood pressure. It is available only by prescription and under strict supervision by a medical professional.

Sanorex

Sanorex (mazindol) is an FDA-approved drug that works two ways: it reduces appetite while increasing blood pressure and causing your metabolism to work harder and faster. Meant to be used as a short-term aid and used alongside exercise and diet, Sanorex is known as an anorexiant because of its ability to suppress appetite almost completely. Sanorex is highly stimulative and addictive and can cause serious side effects, including hallucinations, changes in insulin and tremors. Sanorex should only be used under strict medical supervision, since the drug can interfere with other medications or cause seizures or other health issues.