Cilostazol, naftidrofuryl oxalate, pentoxifylline and inositol nicotinate for the treatment of intermittent claudication in people with peripheral arterial disease

Cilostazol (Pletal, Otsuka Pharmaceuticals) is an oral phosphodiesterase 3 inhibitor. Cilostazol is a direct arterial vasodilator, and it also inhibits platelet aggregation. Cilostazol has a UK marketing authorisation for the 'improvement of the maximal and pain-free walking distances in patients with intermittent claudication, who do not have rest pain and who do not have evidence of peripheral tissue necrosis'. Cilostazol is contraindicated in people with severe renal impairment (creatinine clearance of 25 ml/min or lower), moderate or severe hepatic impairment, congestive heart failure and pregnancy. Cilostazol is also contraindicated in people with any known predisposition to bleeding or with any history of ventricular tachycardia, ventricular fibrillation or multifocal ventricular ectopic beats. For full details of side effects and contraindications see the summaries of product characteristics.

Cilostazol is available as a 50 or 100 mg tablet at a cost of £35.31 for a 56-tablet pack (price for either dose, excluding VAT; BNF, edition 60). The recommended dose is 100 mg twice daily. Therefore, assuming 100 mg tablets are used, the average monthly cost is £38.26. Costs may vary in different settings because of negotiated procurement discounts.

Naftidrofuryl oxalate (Praxilene, Merk Serono) is an oral peripheral vasodilator that selectively blocks vascular and platelet 5-hydroxytryptamine 2 (5-HT2) receptors. Naftidrofuryl oxalate has a UK marketing authorisation for 'peripheral vascular disorders – intermittent claudication, night cramps, rest pain, incipient gangrene, trophic ulcers, Raynaud's syndrome, diabetic arteriopathy and acrocyanosis'. Naftidrofuryl oxalate is contraindicated in people with a history of hyperoxaluria or recurrent calcium-containing stones. For full details of side effects and contraindications see the summary of product characteristics.

Naftidrofuryl oxalate is available as a branded preparation of 100 mg capsules at a cost of £8.10 for an 84-capsule pack (excluding VAT; BNF edition 60). Generic preparations are also available at a cost of £5.30 (excluding VAT; BNF edition 60), and since January 2011 at a cost of £4.52 (excluding VAT; BNF edition 61) for a 100 mg 84-capsule pack. The recommended dose is one or two 100 mg capsules 3 times daily. Therefore, for the branded preparation the average monthly cost is £8.80 assuming three 100 mg capsules daily or £17.89 assuming six 100 mg capsules daily. For the generic preparation (that is at a cost of £5.30, excluding VAT; BNF edition 60) the average monthly cost is £4.90 for three 100 mg capsules daily or £9.79 assuming six 100 mg capsules daily. Costs may vary in different settings because of negotiated procurement discounts.

Pentoxifylline (Trental 400, Sanofi-Aventis) is an oral peripheral vasodilator derived from methylxanthine. Pentoxifylline has a UK marketing authorisation for the 'treatment of peripheral vascular disease, including intermittent claudication and rest pain'. Pentoxifylline is contraindicated in people with cerebral haemorrhage, extensive retinal haemorrhage, acute myocardial infarction and severe cardiac arrhythmias. For full details of side effects and contraindications see the summary of product characteristics.

Pentoxifylline is available as a 400 mg tablet at a cost of £19.68 for a 90-tablet pack (excluding VAT; BNF edition 60). The recommended dose is 1 tablet 3 times daily. Therefore, the average monthly cost is £19.90. However, the summary of product characteristics states that 2 tablets daily may prove sufficient in some patients, particularly for maintenance therapy. Costs may vary in different settings because of negotiated procurement discounts.

Inositol nicotinate (Hexopal, Genus Pharmaceuticals) is an oral peripheral vasodilator that slows the release of nicotinic acid. Inositol nicotinate has a UK marketing authorisation for 'the symptomatic relief of severe intermittent claudication and Raynaud's phenomenon'. Inositol nicotinate is contraindicated in people who have suffered a recent myocardial infarction or are in the acute phase of a stroke. For full details of side effects and contraindications see the summaries of product characteristics.

Inositol nicotinate is available as a 500 mg tablet at a cost of £30.76 for a 100-tablet pack. It is also available as a 750 mg tablet at a cost of £51.03 for a 112-tablet pack (excluding VAT; BNF edition 60). The recommended dose is 3 g daily (that is, two 500 mg tablets 3 times a day), increased to 4 g daily if necessary. The average monthly cost, assuming two 500 mg tablets 3 times a day, is £56.14. Costs may vary in different settings because of negotiated procurement discounts.