Prescription Weight Loss Drugs
In addition to diet and exercise, your weight loss doctor may prescribe certain types of medications to help you lose weight. Learn more about the types of prescription weight loss medications available, how they work, and who should consider taking them.
Types of Prescription Weight Loss Medications
Most prescription weight loss drugs fall into one of two categories: appetite suppressants or fat absorption inhibitors.
- Appetite suppressants are the most common type of weight loss medications prescribed. They usually come in the form of tablets or extended-release capsules, which release medication into the bloodstream over a period of time. Appetite suppressants are designed to trick the body into believing that it’s full or not hungry. Usually, this is done by increasing serotonin or catecholamine – “two brain chemicals that affect mood and appetite. The goal of appetite suppressants is to help you lose weight by eating less. Meridia is a commonly prescribed appetite suppressant.
- Fat absorption inhibitors, on the other hand, work by preventing your body from breaking down and absorbing the fat that you do eat. This unabsorbed fat is then eliminated through bowel movements. Xenical is the only fat absorption inhibitor approved for use in the United States, and it is now available over the counter as Alli. While Xenical blocks the absorption of fat in the body, it also reduces the absorption of some vitamins. People who take fat absorption inhibitors may need to take additional supplements to make up for this reduced vitamin absorption.
Who Should Take Prescription Weight Loss Medications?
Weight loss medications are considered to be moderately effective, generating a weight loss of 5 to 22 pounds in a year. This may be a positive solution for someone who is considered moderately obese, but may not be sufficient for severely obese people. In general, prescription weight loss medications are reserved for people with a body mass index of 30 and above with no obesity-related conditions, or people with a BMI of 27 and above with obesity-related health problems.
Prescription Weight Loss Medication Side Effects
As with many prescription medications, there is a potential for weight loss medications to cause side effects. While these side effects are generally mild and temporary, it’s important to be aware of your individual risk. If you have a history of high blood pressure, heart disease, irregular heartbeat, or stroke, for example, you’re at an increased risk for complications with appetite suppressants and should seek another weight loss solution. People who are taking fat absorption inhibitors should eat a low-fat diet and take a daily multivitamin in order to decrease their risk for unpleasant side effects.
Side effects for appetite suppressants include:
- Increased heart rate
- Increased blood pressure
- Insomnia (inability to sleep or stay asleep)
- Excessive thirst
- Stuffy nose
- Dry mouth
Side effects for fat absorption inhibitors include:
- Abdominal cramping
- Oily stool
- Increased number of bowel movements
- Inability to control bowel movements; leakage of oily stool
Because of the risk of side effects, addiction, and developed tolerance, weight loss drugs are usually prescribed on a short-term basis. Most people will notice a plateau in their weight loss after six months on prescription weight loss medications. It’s important, then, that people who are taking weight loss medications use this time to develop new eating and exercise habits if they want to continue to lose weight and keep the weight off in the long-term.