A popular anti-HIV drug, Abacavir, appears to dramatically increase the risk of heart attack, a new study says. The anti-retroviral drug is used in many anti-AIDS regimens worldwide but Danish researchers have found that it almost doubled patients' chances of heart problems.

In a study published online Tuesday in The Lancet medical journal, European researchers said patients may wish to consider changing treatment programs after studying more than 33,000 patients using the drug. The lesser-used drug didanosine also increased the heart attack risk by about 50 percent

HIV drugs manufactured by GlaxoSmithKline and Bristol-Myers Squibb are being reviewed by the U.S. Federal Drug Administration after a study connected the drugs to increased risk of heart attack.

The study of 33,000 HIV patients, which was done to determine the short and long term risk of taking AIDS drugs, revealed that patients taking Ziagen (a GlaxoSmithKline drug) and Videx (a Bristol-Myers Squibb drug) were at increased risk of heart health problems when compared to other types of treatment

The Food and Drug Administration grants tentative approval of generic abacavir sulfate tablets to treat HIV.

The drug is the first generic version of Ziagen Tablets, an anti-HIV medication already approved by the FDA