MedicinerestrictedEssential

Cycloserine

A second-line antibiotic for tuberculosis when standard medicines are inadequate.

Clinical information

Common uses

active tuberculosis (always with other TB drugs)
certain resistant urinary tract infections

Common side effects

drowsiness and sleepiness
headache
tremor
dizziness (vertigo)
confusion or disorientation

Cautions

not with epilepsy, depression, severe anxiety or psychosis
stop or reduce if seizures or mental changes develop
alcohol increases seizure risk
avoid with severe kidney problems

Interactions

alcohol — excessive use raises seizure risk

Reference information, not medical advice — always follow your doctor or pharmacist. Source: DailyMed, dailymed.nlm.nih.gov, cycloserine capsule label, setid 8e7e2665-7a3d-3f54-9f92-5fe845f02ef9 (accessed 2026-08-16)

Approved brands & formulations5

Brand name	Dosage form	Strength	Importer	Category
Cycloserine	Capsule	250mg	—	restricted
Cycloserine	Capsule	250mg	—	restricted
Cycloserine	Tablet	500 mg	—	restricted
Cycloserine	Capsule	125mg	—	restricted
Cycloserine	Capsule	125mg	—	restricted