TNF and Opportunistic infection: The most commonly used drugs in CD are corticosteroids, immunosuppressants (thiopurines [azathioprine and mercaptopurine] and methotrexate), biologicals (anti-TNF (tumor necrosis factor) [infliximab, adalimumab, and certolizumab pegol], and anti-adhesion molecules (vedolizumab).[9] While anti-TNF therapy appears to be the most effective therapy, used alone or in combination with an immunomodulator to induce and maintain remission in moderate to severe CD,[5] it was shown to double the risk of opportunistic infections[10] and might increase the risk of melanoma skin cancer.[11]