Clinical trial, with positive findings,  conducted at a university health clinic in South Africa on 30 adult  subjects with an allergy to cats. Half of the subjects were randomly  allocated to receive a homeopathic combination of cat saliva and  histamine; the other half received a dummy medicine (placebo). They did  not know which treatment group they were in. After 4 weeks, the subjects  who received the homeopathic medicine had a lesser degree of  inflammation (wheal) after a skin-prick test than those who received  placebo.

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