Two hundred and fifteen patients with chloroquine-resistant malaria were randomised into three groups. The first group of 82 patients were given pyrimethamine and berberine (berberine group), the second group of 64 patients, pyrimethamine and tetracycline (tetracycline group) and the third group of 69 patients were given pyrimethamine and cotrimoxazole (cotrimoxazole group). In the berberine group, the clearance, rate of asexual parasitaemia was 74.4% after treatment, while in the tetracycline group it was 67.2% and in the cotrimoxazole group 47.8%. These results indicate that berberine is more effective in clearing the parasite than both tetracycline and cotrimoxazole, and that the combination of pyrimethamine and berberine gives the best results for chloroquine resistant malaria.