Avandamet and Weight Gain
Before medicines are approved, they must go through several clinical studies where thousands of people are given a particular medicine and compared to a group of people not given the medicine. In these studies, side effects are always documented. This way, it is possible to see what side effects occur, how often they appear, and how they compare to the group not taking the medicine.
In clinical studies, people taking Avandamet did not gain weight (on average). However, some people lost up to 7.5 pounds, while others gained up to 6.5 pounds. Weight gain with the use of Avandamet is likely due to the rosiglitazone component of Avandamet, since rosiglitazone has been shown to cause weight gain. Weight loss while taking Avandamet is likely due to the metformin component of Avandamet, since metformin may actually cause weight loss (see Metformin and Weight Loss). More people gained weight with Avandamet doses that contained higher doses of the rosiglitazone component.
When talking about Avandamet and weight gain, remember that Avandamet may worsen congestive heart failure or, in some cases, even cause the serious condition. One of the main symptoms of heart failure is unexplained weight gain. In fact, people with symptoms of congestive heart failure can often have rapid weight gain (three to five pounds) over several days. This weight gain is often combined with other symptoms, such as a cough and/or swelling in the ankles, feet, or legs. Make sure to contact your healthcare provider if you notice unexplained weight gain or swelling (see Symptoms of Congestive Heart Failure for more information on heart failure symptoms).