Federal health officials indicate that side effects of Xeljanz, a popular rheumatoid arthritis and ulcerative colitis drug, may increase the risk of blood clots in the lungs, potentially resulting in a pulmonary embolism or death. The FDA’s Xeljanz warning was issued Monday, after a recent clinical trial found that patients taking certain dosage amounts of Xeljanz for rheumatoid arthritis were found to be more likely to develop blood clots or die, when compared to individuals taking the same doses of the drug to treat ulcerative colitis. Xeljanz (tofacitinib) is a drug that was first approved by the FDA in 2012…