Popular anti-inflammatory drug Vioxx will be withdrawn from the market, drug-maker Merck & Co. announced Thursday. Many senior citizens use the drug for arthritis relief.

The voluntary withdrawal comes after a three-year study found that patients taking the drug face twice the risk of heart attack and stroke compared to participants taking a placebo. Researchers were conducting the study on patients at risk of developing reoccurring colon polyps.

The Federal Drug Administration acknowledged the withdrawal and issued a public health advisory about Vioxx. The FDA will monitor similar drugs in this sector, said acting FDA commissioner Dr. Lester Crawford.