Is herbal arnica of benefit in bruising?
Q - Is arnica an effective remedy for bruising?
A - Arnica is quite poisonous. Taken orally it can cause irritation of mucous membranes, drowsiness, stomach pain, vomiting, diarrhoea, tachycardia, shortness of breath, coma and death.
Topically, arnica can cause contact dermatitis and mucous membrane irritation. Don't take it orally unless homoeopathically diluted beyond Avogadro's number (the number of molecules in a mole: 6.022 x 1023).
There are several herbal arnica creams and there is some preliminary data to suggest these might have an effect on bruising. But this evidence is unconvincing. Arnica flower and extracts are believed to be antibacterial, anti-inflammatory, an immune stimulant, and cardiotonic.
Creams vary in potency. The limited evidence applies to all creams and strengths.
The evidence for the efficacy of oral homoeopathic arnica is not uniform.
There are about a dozen controlled clinical trials and the sum of the evidence does not show that homoeopathic arnica has more than a placebo effect.
Edzard Ernst is professor of complementary medicine,
Peninsula Medical School,