The quality of evidence is downgraded by study limitations (unclear allocation concealment and blinding, selective outcome reporting), and by inconsistency (unexplained variability in results).
A Cochrane review included 24 studies with a total of 3377 subjects. Seventeen studies compared pentoxifylline versus placebo. In the seven remaining studies, pentoxifylline was compared with flunarizine (one study), aspirin (one study), Gingko biloba extract (one study), nylidrin hydrochloride (one study), prostaglandin E1 (two studies) and buflomedil and nifedipine (one study). Pooled analysis was not possible due to considerable heterogeneity between the included studies with regards to multiple variables including duration of treatment, dose of pentoxifylline, baseline walking distance and patient characteristics.
In a total of 17 studies which compared pentoxifylline with placebo, of which 14 reported total walking distance (TWD) and 11 reported to pain-free walking distance (PFWD), the difference in percentage improvement in TWD for pentoxifylline over placebo ranged from 1.2% to 155.9%, and for PFWD the difference ranged from -33.8% to 73.9%. Testing for statistical significance of these results was generally not possible due to the lack of data. There was no statistically significant difference in ankle brachial pressure index (ABI) between the pentoxifylline and placebo groups. Pentoxifylline was generally well tolerated.
Exercise is the treatment of choice, and it is unclear whether oral pentoxifylline confers additional benefits to patients who can and do participate in therapeutic exercise regimens.