Two large clinical trials analyzing the effects of the arthritis medication Enbrel in the treatment of congestive heart failure (CHF) were recently halted in Europe due to the possibility that the drug may worsen a patient's condition. Physicians in the United Kingdom are now being advised to "use caution" when prescribing the drug because of postmarketing reports of "worsening of CHF, with and without identifiable precipitating factors." Enbrel has been linked to serious reactions, including the development of angioedema and urticaria as well as sepsis, lupus and MS. Enbrel has also been linked to the development of anemia.