The effects of some alkaloids and flavonoids, which are major ingredients in some of the Japanese Kampoh drugs (Japanese-Chinese traditional herbal medicines) experientially known to be efficacious for the treatment of acne vulgaris, on the lipogenesis in the sebaceous glands of the hamster ear, an excellent animal model for the human sebaceous gland, were studied. Lipogenesis was assayed by determining 14C incorporation into sebaceous lipids extracted from the sebaceous glands which were preincubated with 14C-acetate. We found that the lipogenesis in the hamster sebaceous glands was suppressed 63 and 54% by 10-4M berberine (an alkaloid) and wogonin (a flavonoid), respectively. We suggest that the therapeutic effects of some Japanese Kampoh drugs experientially used for acne vulgaris could be due to inhibition of lipogenesis by their active ingredients such as berberine and wogonin.