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Seromycin Side Effects

Generic Name: cycloserine

Note: This document contains side effect information about cycloserine. Some of the dosage forms listed on this page may not apply to the brand name Seromycin.

For the Consumer

Applies to cycloserine: oral capsule

Along with its needed effects, cycloserine (the active ingredient contained in Seromycin) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking cycloserine:

More Common

Less Common

Some side effects of cycloserine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More Common

For Healthcare Professionals

Applies to cycloserine: oral capsule


Cycloserine (the active ingredient contained in Seromycin) is most frequently associated with neurotoxicity and hypersensitivity.[Ref]

Nervous system

Nervous system side effects may be dose-related (> 500 mg/day) and have included convulsions, drowsiness, somnolence, headache, tremor, dysarthria, vertigo, confusion, disorientation, loss of memory, psychoses, suicidal tendencies, character changes, hyperirritability, aggression, paresis, hyperreflexia, paresthesia, major and localized seizures, and coma.[Ref]


Hematologic side effects have included vitamin B12 deficiency, folic acid deficiency, megaloblastic anemia, and sideroblastic anemia.[Ref]


Hepatic side effects have included elevated serum transaminases, particularly in patients with preexisting liver disease.[Ref]


Hypersensitivity reactions have included skin rash.[Ref]


Cardiovascular side effects have included sudden development of congestive heart failure in patients receiving high doses (1 to 1.5 g/day).[Ref]


1. "Product Information. Seromycin (cycloserine)." Dura Pharmaceuticals, San Diego, CA.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.