Weight loss drug phentermine, safe and effective for long term use: Study

A study recently found that the weight loss drug called Phentermine, which can only be used for a short while, may also be safe and effective for longer-term treatment.

The inexpensive drug Phentermine is FDA approved to use. However, it can only be used for a period of three months and no longer than that. The researchers tried to understand how the long term use of this drug affects the general population. This study was published in the journal Obesity.

The lead author Kristina H. Lewis said, "Although diet and exercise are critical components of any weight-loss program, up to half of the patients don't have long-term success with lifestyle changes alone. In some cases, medications or surgery can help. Generic phentermine is an effective and affordable option, but now that we view obesity as a chronic disease, it's important to have medications that can be used indefinitely. Most new weight-loss drugs are approved for long-term use, but unfortunately, the newer drugs can be expensive if they are not covered by insurance."

The researchers analyzed data from the electronic health records of 13,972 adults who were prescribed phentermine for short-term use versus longer-term use of a year or more. The people whose records were analyzed in the study did not have evidence of pre-existing heart disease and most were young or middle-aged women.

They then compared weight loss and changes in blood pressure for up to two years, and the risk of heart attack, stroke or death for up to three years, according to a patient's duration of medication use.

The researchers found that people who stayed on phentermine longer experienced greater weight loss than those who took the drug for three months or less, and longer-term use was not associated with increases in blood pressure or increased risk of heart attack, stroke or death.

"In general, the longer patients were on the medicine the more weight loss they had, not surprisingly, when patients stopped taking the medicine weight was regained, "said Lewis.

However, the researchers cautioned that phentermine is a stimulant and should not be used in people with a history of heart disease, stroke or uncontrolled high blood pressure. But for those with low cardiac risk, normal blood pressure or high blood pressure that is well treated, it could be a good and affordable option.