NEW YORK (Reuters Health) April 16 Pentoxifylline therapy provides only limited efficacy against recurrent aphthous stomatitis and should not be considered a first-line agent, new research indicates. However, the drug may be considered if other treatments prove unsuccessful. As researchers note in the April issue of Archives of Dermatology, pentoxifylline has effects similar to both thalidomide and colchicine, two agents that have proven effective in some patients with recurrent aphthous