Pentoxifylline (
oxpentifylline) has been used widely in the treatment of
intermittent claudication, a prevalent condition in the elderly population. The exact mechanism(s) of action of the
drug are unclear, but may be related to identified effects on white blood cell function and haemorrheological parameters. Clinical trials which conform best with European and North American guidelines have shown that 6 months' oral
therapy with
pentoxifylline 1200 mg/day significantly improves walking distances in patients with
intermittent claudication. Patients most likely to benefit from treatment are those with an ankle/arm blood pressure ratio < or = 0.8 and a history of disease > 1 year. However, it remains unclear whether
pentoxifylline or any other
conservative treatment approach (including physical training) offers long term benefit, as studies comparing the development of
intermittent claudication after several years of treatment with the natural course of the disease are still lacking. In patients with more severe
vascular disease,
intravenous administration of
pentoxifylline (1200 mg/day for 21 days) decreased rest
pain in patients with critical limb ischaemia.
Oral administration (1200 g/day for up to 6 months) increased the healing of
venous ulcers of the leg when used as an adjunct to standard compression bandaging. However, further studies are required to confirm these initial findings. The efficacy of
pentoxifylline in the treatment of
cerebrovascular disease has been evaluated in controlled clinical trials. Most notably, long term
therapy (1200 mg/day) may slow the progression of
dementia in patients who meet the clinical diagnostic criteria for '
multi-infarct' dementia and who also have clinical and neuroradiological evidence of
cerebrovascular disease. The
drug is effective in decreasing the risk of transient ischaemic attacks, but there are insufficient data to determine its value in the prevention and treatment of
stroke.
Pentoxifylline is well tolerated, with gastrointestinal effects reported in fewer than 3% of treated patients. However, the incidence of adverse events may be higher in elderly patients and/or those receiving concomitant medications. In summary,
pentoxifylline is the most established agent when
drug therapy is deemed appropriate in patients with
intermittent claudication. Moreover, a promising new development for the
drug is in the management of cerebrovascular
dementia, an area where few therapeutic options are currently available.