Lane P, Williamson D M
Br Med J. 1969 Apr 12;2(5649):76-9. doi: 10.1136/bmj.2.5649.76.
Fifty-one patients with acne vulgaris were included in a double-blind trial to assess the therapeutic effect of 250 mg. tetracycline hydrochloride twice daily for three months. The results, assessed clinically and photographically, showed that tetracycline hydrochloride had a statistically significant beneficial effect. Hence, since it is cheap and rarely has side-effects in healthy young adults, its use is suggested, as well as local therapy, in the more severe forms of acne.