Extensive studies have been done with Ginkgo biloba extracts (GBE) for treatment of intermittent claudication.^1,2 Two double-blind trials found that 120 mg of GBE per day increased pain-free and total walking distance among people with intermittent claudication.^3,4Similar results were seen in another double-blind trial using 160 mg of GBE per day.⁵ In yet another double-blind trial, two doses of ginkgo extract were compared for six months.⁶ The researchers studied 60 vs. 120 mg twice daily and found that, while both amounts resulted in significant improvements in pain-free walking distance, the improvements were more pronounced at the higher dose. One double-blind study found that ginkgo extract was not beneficial.⁷ However, that study lasted only three months, whereas the positive studies lasted six months. It may take longer than three months for ginkgo to have a beneficial effect in people with intermittent claudication.

Inositol hexaniacinate (IHN), a special form of vitamin B3, has been used successfully to treat intermittent claudication. The alleged advantage of IHN over niacin (another form of vitamin B3) is a lower risk of toxicity. A double-blind trial explored the effect of 2 grams of IHN taken twice per day for three months.⁸ In nonsmokers and in people with unchanged smoking habits, the increase in walking distance was significantly greater in the IHN group than in the placebo group. Other double-blind research has confirmed IHN’s ability to improve symptoms of intermittent claudication compared with placebo.⁹ This treatment should be monitored by a doctor.

Policosanol, taken in the amount of 10 mg twice a day for at least six months, increases pain-free walking capacity by over 50% in people with intermittent claudication according to two double-blind trials.^10,11 When policosanol was taken continuously for two years, walking capacity more than doubled.¹⁰ This effect may be related to the ability of policosanol to reduce the stickiness of platelets,^13,14,15 which could result in improved circulation.

Vitamin E supplementation has been shown in controlled trials to increase both walking distance and blood flow through arteries of the lower legs in people with intermittent claudication.^15,16 Increasing dietary intake of vitamin E was also associated with better blood flow to the legs.¹⁷ Some early studies did not find vitamin E useful. Possibly this failure was due to the short duration of the studies,¹⁸ as one review article suggested that a minimum of four to six months of vitamin E supplementation may be necessary before significant improvement is seen.¹⁹ Most clinical trials of vitamin E and intermittent claudication used 400 to 600 IU per day, although one study used 2,400 IU per day.

Men with intermittent claudication consumed a fortified milk product or regular milk daily for one year. The fortified product provided daily 130 mg of eicosapentaenoic acid and 200 mg of docosahexaenoic acid (EPA and DHA, two fatty acids in fish oil), small amounts of supplemental vitamin E, folic acid, and vitamin B6, and additional amounts of oleic acid and alpha-linolenic acid. Compared with regular milk, the fortified milk product significantly increased the distance the participants could walk before the onset of pain.²⁰

A standardized extract of garlic has been tested as a treatment for intermittent claudication. In a double-blind trial, the increase in walking distance was significantly greater in people receiving garlic powder extract (400 mg twice per day for 12 weeks) than in those given a placebo.²¹

In double-blind trials, supplementation with either L-carnitine and propionyl-L-carnitine (a form of L-carnitine) has increased walking distance in people with intermittent claudication. Walking distance was 75% greater after three weeks of L-carnitine supplementation (2 grams taken twice per day), than after supplementation with a placebo, a statistically significant difference.²² In the study using propionyl-L-carnitine, improvement occurred only in those who could not walk 250 meters to begin with. In that group, maximum walking distance increased by 78% with propionyl-L-carnitine supplementation compared with a 44% increase in the placebo group, also a statistically significant difference.²³ The amount of propionyl-L-carnitine used was 1 gram per day, increasing to 2 grams per day after two months, and 3 grams per day after an additional two months, if needed. The results of this trial have been confirmed in a large European trial.²⁴

In a double-blind trial, people with intermittent claudication received 760 mg twice daily of the Tibetan herbal formula Padma 28® or a placebo for 16 weeks. The average walking distance increased by 115% among people receiving Padma 28, compared with a 17% increase in the placebo group (a statistically significant difference). No side effects were reported.²⁵ Padma 28 was also found to increase walking distance in a second study.²⁶

Caution: One study showed a slightly increased risk of vascular surgery among people with intermittent claudication who took beta-carotene supplements.²⁷ Until more is known, people with intermittent claudication wishing to use beta-carotene supplements should first consult with their doctor.

Magnesium may increase blood flow by helping to dilate blood vessels. A preliminary trial found that magnesium supplementation may increase walking distance in people with intermittent claudication.²⁸ Many doctors suggest that people with atherosclerosis, including those with intermittent claudication, take approximately 250 to 400 mg of magnesium per day.

In a preliminary trial, supplementing with evening primrose oil (approximately 1,600 mg per day) led to a 10% increase in exercise tolerance in people with intermittent claudication.²⁹