Serious Side Effects Linked to Avandia, Fosamax

Two new studies have linked the popular prescription drugs Fosamax and Avandia to serious side effects, Reuters reports. Fosamax, prescribed for osteoporosis, has been tied to a type of abnormal heartbeat that can cause dizziness and fatigue. Another study links Avandia, used to treat diabetes, to a double or even triple risk of broken limbs after long-term use.

Fosamax maker Merck said in a statement that the company's own clinical trial did not find a statistically significant link between an abnormal heartbeat and Fosamax.  "We strongly recommend that if patients have concerns about Fosamax they talk to their physician," the statement added.