antitubercular /-to͝obur″kyələr/ , any agent or group of drugs used to treat tuberculosis. At least two drugs, and usually three, are required in various combinations in pulmonary tuberculosis therapy. These include isoniazid, ethambutol hydrochloride, streptomycin sulfate, and rifampin. Supplements of pyridoxine (vitamin B6) also may be needed to relieve the symptoms of peripheral neuritis that can occur as a side effect of isoniazid.
