Cycloserine is a tablet-form anti-mycobacterial drug, which is used in combination with other drugs for treating multi-drug-resistant tuberculosis. Its side-effects can include mood disturbances, headache, dizziness, vertigo, drowsiness, shakes, convulsions, psychosis, depression, rashes and changes in liver functioning.

It is manufactured by Lilly under the trade name Cycloserine, or, in the United States, Seromycin.