Herbals to treat psoriasis: A review of the evidence

Dr. Sharon Jacob from the University of Miami/Jackson Memorial Medical Center in Florida and colleagues reviewed the scientific support for herbals used by patients with psoriasis.

Here are the highlights.

Cayenne (Capsicum annuum, Capsicum frutescens)

• 2 studies showed improvement with topical application.
• Unfortunately, burning and stinging at the application sites in the capsicum group made impossible to blind the study.

Aloe (Aloe vera)

• In one study, the aloe group showed significantly higher rates of clearing of psoriatic plaques (83%) vs placebo (7%).
• Delayed hypersensitivity reactions are a reported complication of topical aloe.

Dong quay (Angelica sinensis)

• It contains a psoralen that acts as a potent photosensitizer in the presence of UVA.
• In 92 patients, two-thirds experienced complete clearing of their disease after oral treatment
• Caution in patients who are pregnant or using oral contraceptives, as bleeding and drug-herb interactions have been noted.
• Another herb (hogweed; Heracleum sphondylium) contains a psoralen, but data are not available for this herb.

Milk thistle (Silybum marianum)

• Not proven to directly benefit psoriasis.
• Might protect the liver in patients on hepatotoxic medications.
• Diarrhea, uterine stimulation, and herb-drug interactions with butyrophenones, phenothiazines, yohimbine, and phentolamine have been reported.

Slippery elm (Ulmus rubra)

• Reported improvement could not be attributed to the effects of slippery elm alone.

Evening primrose (Oenothera biennis)

• Studies show no effectiveness.

Turmeric/Indian saffron (Curcuma longa, Curcuma domestica)

• Clearing of plaques has not been studied.

No studies available in psoriasis for the following herbals.

• Chamomile (Matricaria recutita)
• Tea tree oil (Melaleuca alternifolia)
• Wintergreen/Boxberry (Gaultheria pro cumbens)

Read the article for more detail and a table of herbal adverse effects and interactions.

12/18/07 23:33 JR