In clinical studies that looked at possible side effects of Fosamax, there did not seem to be a relationship between Fosamax and weight gain. This was not reported as either a common or rare side effect, nor has weight gain been reported by healthcare providers since the drug was approved.

Fosamax and Weight Gain: An Overview

Fosamax^® (alendronate sodium) is a prescription medication used to treat Paget's disease, as well as to treat and prevent osteoporosis. As with all medications, the drug can have side effects (see Fosamax Side Effects). However, weight gain does not appear to be one of them. This information comes from clinical trials where Fosamax was extensively studied and side effects were carefully documented.

 

Before medicines are approved, they must go through several clinical studies, where a large number of people are given a particular medicine and compared to a group of people given a placebo (a "sugar pill"). In these studies, any possible side effect is always carefully documented. This way, it is possible to see what side effects occur, how often they appear, and how they compare to the group taking the medication and the group taking the placebo. Side effects are then usually separated into those that occur in more than 1 percent of people (common side effects) and those that occur in less than 1 percent of people (rare side effects).

 

In studies, weight gain was not reported as either a common or a rare side effect of Fosamax. Also, weight gain was not among the possible additional side effects that were reported by healthcare providers after the medication was approved.