Methaniazide, brand name Neotizide among others, is an antibiotic which was used in the treatment of tuberculosis.

[1][2][3] It is a derivative of methanesulfonic acid and isoniazid, which is also an antituberculosis drug but has comparatively been far more widely known and used.

[4] Methaniazide features its mesylate group at the same position as that of the acetyl group in acetylisoniazid, and so methaniazide probably acts as a prodrug of isonicotinic acid similarly to isoniazid and acetylisoniazid.

[5] Neothetazone is an antibiotic combination of methaniazide (neotizide) and thioacetazone which was previously used in the treatment of tuberculosis.

[6][7][8] Similarly, there have been a variety of case reports in the literature of gynecomastia associated with isoniazid treatment.