Phentermine is currently produced by several different manufacturers.
Phentermine works by suppressing the appetite, and it may also increase the metabolism. It is chemically related to amphetamines.
Only very short studies have evaluated the effectiveness of medications like phentermine. In these studies, people taking these medications lost more weight than those not taking them, but the difference was small (only a fraction of a pound more per week for the people taking the weight loss medication). Studies also suggest that the effects of these medications for weight loss decrease after the first few weeks.
General considerations for when and how to take phentermine include the following:
- Phentermine comes in tablet and capsule form. It is usually taken by mouth once daily, although some people may need to take it twice a day.
- The medication should be taken either before breakfast or one to two hours after breakfast, depending on the particular phentermine product.
- Phentermine should be combined with an appropriate diet. It is not meant to be used without dieting.
- Do not take phentermine more often (or at higher doses) than prescribed, as this can lead to addiction or dependence.
- For the medication to work properly, it must be taken as prescribed.
The dose of phentermine your healthcare provider recommends will vary, depending on a number of factors, including:
- The particular phentermine product
- How you respond to the medication
- If you develop bothersome or dangerous side effects
- Other medical conditions you may have
- Other medications you may be taking.
As is always the case, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
(Click Phentermine Dosage for more information.)