Diet pills are drugs that are taken to help weight loss. Many diet pills are considered appetite suppressants. These drugs suppress the appetite by altering the level of chemicals in the brain associated with feeling full. Other diet pills may increase the body’s metabolism. This helps a person to lose weight by increasing the amount of fat that is used as energy, thereby reducing the amount of fat absorbed by the body.

The Food and Drug Administration (FDA) has approved several medications that a physician may prescribe to treat obesity. One type helps people lose weight by preventing the absorption of fat. In 2007, a lower-dose version of this drug became the only FDA-approved diet pill that does not require a prescription.

In most cases, these medications are for short-term use for people who have health conditions that are worsened by being overweight, such as diabetes, high blood pressure or heart conditions. Both short-term and long-term diet pills should be used along with healthy diet and exercise.

There are also over-the-counter diet pills not approved by the FDA that claim to help people lose weight. Their effectiveness and safety has not been fully tested. In some cases, these pills have had severe and even fatal side effects.

Diet pills may have side effects that range from mild to severe. Some of the most common side effects include irritability, nervousness, elevated blood pressure and gastrointestinal problems (e.g., constipation, diarrhea, stomach cramps). Additionally, patients should be aware of signs of dependency such as a strong desire for the medication, a need for the dosage to be increased to obtain the same results and the occurrence of withdrawal symptoms when the medication is stopped.

Diet pills may not be suitable for some people. This may include women who are pregnant or who are breastfeeding, elderly people and children under 18. Some diet pills may also be unsafe for people with certain health conditions, including high blood pressure, cardiovascular disease and a history of stroke. Patients should consult their physician before taking either prescription or over-the-counter diet pills.