We describe 120 patients with regional lymphadenitis following intradermal BCG vaccination. Seventy-eight of the patients were given medical therapy to prevent drainage and suppuration, and 42 patients were followed up without such treatment. The medical therapy group is divided into three subgroups: 36 were given erythromycin stearate, 21 isoniazid, and 21 isoniazid plus rifampin. No statistical difference in the incidence of spontaneous drainage and suppuration was found between the "no therapy" and the "medical therapy" groups. No significant superiority of any specific therapy was shown. If lymphadenitis develops rapidly (in two months), the incidence of spontaneous drainage and suppuration is significantly higher than in patients with slowly developing lesions. Total surgical excision is recommended to prevent spontaneous drainage and chronic suppuration in these rapidly evolving instances.