Dosing & Uses
Dosage Forms & Strengths
capsule
- 250mg
Active Tuberculosis
Initial: 250 mg PO q12hr for 14 days THEN
500 mg -1 g/day divided q12hr for 18-24 months; not to exceed 1 g/day
Monitor blood levels
UTI
Initial: 250 mg PO q12hr for first 14 days
Maintenance: 500 mg -1 g/day in divided doses; not to exceed 1 g/day
Monitor blood levels
Gaucher's Disease (Orphan)
Orphan indication sponsor
- Lev, Meir M.D.; The City College, City University Of NY Medical Sc, Convent Avenue at 138 Street; New York, NY 10031
Renal Impairment
CrCl 50-80 mL/min: Administer q12-16hr
CrCl 10-49 mL/min: Administer q24-36hr
CrCl <10 mL/min: Administer q36-48hr
Administration
Part of multi-drug regimen; not first-line treatment
Dosage Forms & Strengths
capsule
- 250mg
Active Tuberculosis
10-20 mg/kg/day PO in divided doses up to 1 g/day for 18-24 months
Renal Impairment
CrCl 50-80 mL/min: Administer q12-16hr
CrCl 10-49 mL/min: Administer q24-36hr
CrCl <10 mL/min: Administer q36-48hr
Administration
Part of multi-drug regimen; not first-line treatment
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (0)
Serious - Use Alternative (0)
Monitor Closely (3)
- ethionamide
ethionamide, cycloserine. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Enhanced CNS toxicity; risk of seizure.
- isoniazid
isoniazid increases toxicity of cycloserine by decreasing metabolism. Use Caution/Monitor. Enhanced CNS toxicity; risk of seizure.
- sodium picosulfate/magnesium oxide/anhydrous citric acid
cycloserine decreases effects of sodium picosulfate/magnesium oxide/anhydrous citric acid by altering metabolism. Use Caution/Monitor. Coadministration with antibiotics decreases efficacy by altering colonic bacterial flora needed to convert sodium picosulfate to active drug.
Minor (0)
Adverse Effects
Frequency Not Defined
Confusion
Restlessness
Drowsiness
Vertigo
Cardiac arrhythmia
Folate deficiency
Hyperreflexia
Dysarthria
Dizziness
Headache
Coma
Liver enzymes increased
Somnolence
Paresis
Seizure
Heart failure
Warnings
Contraindications
Hypersensitivity
Alcohol use
Renal dysfunction, severe
History of seizure disorder, mental depression, severe anxiety or psychosis
Cautions
Caution in patients with history of alcoholism (may increase seizures), anemia, impaired hepatic/renal function
CNS toxicity (depression, seizures, psychosis) may occur
Prolonged use may result in fungal or bacterial superinfection (C. difficile-associated diarrhea)
Pregnancy & Lactation
Pregnancy Category: C
Lactation: enters breast milk; safe
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Bacteriostatic or bactericidal
Inhibits cell wall synthesis
Pharmacokinetics
Absorption: 70-90%
Metabolism: Hepatic
Half-life: 10 hr (normal renal function)
Peak plasma serum: 4-8 hr
Excretion: Urine (60 to 70%)
Images
BRAND | FORM. | UNIT PRICE | PILL IMAGE |
---|---|---|---|
cycloserine oral - | 250 mg capsule | ![]() | |
cycloserine oral - | 250 mg capsule | ![]() | |
cycloserine oral - | 250 mg capsule | ![]() | |
cycloserine oral - | 250 mg capsule | ![]() |
Copyright © 2010 First DataBank, Inc.
Patient Handout
cycloserine oral
CYCLOSERINE - ORAL
(sye-klo-SER-een)
COMMON BRAND NAME(S): Seromycin
USES: This medication is used with other medications to treat tuberculosis (TB). In some cases, it may also be used to treat urinary tract infections (UTIs). It works by stopping the growth of bacteria.This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Using any antibiotic when it is not needed can cause it to not work for future infections.
HOW TO USE: Take this medication by mouth with or without food as directed by your doctor, usually twice daily (every 12 hours).The dosage is based on your weight, medical condition, cycloserine blood levels, and response to treatment.For the best effect, take this antibiotic at evenly spaced times. To help you remember, take this medication at the same time(s) every day.Continue to take this medication (and other TB medications) until the full prescribed amount is finished, even if symptoms disappear. Stopping the medication too early or skipping doses may result in a return of the infection and cause the infection to be more difficult to treat (resistant).Your doctor may also direct you to take vitamin B6 (pyridoxine) to help prevent certain side effects from cycloserine. Follow your doctor's instructions carefully.Tell your doctor if your condition lasts or gets worse.
SIDE EFFECTS: Headache, drowsiness, dizziness, or shaking (tremor) may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor right away if you have any serious side effects, including: weakness, mental/mood changes (such as confusion, agitation, hallucination, depression, thoughts of suicide), numb/tingling skin, seizures, irregular heartbeat, symptoms of heart failure (such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain), pale skin.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking cycloserine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: seizures, mental/mood disorders (such as depression, anxiety, psychosis), kidney disease, liver disease, alcohol use.This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).Cycloserine may cause live bacterial vaccines (such as typhoid vaccine) to not work well. Tell your health care professional that you are using cycloserine before having any immunizations/vaccinations.Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.This medication passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, marijuana (cannabis), antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and opioid pain relievers (such as codeine).Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: numb/tingling skin, confusion, agitation, hallucinations, seizures.
NOTES: Do not share this medication with others.Lab and/or medical tests (such as sputum test, cycloserine blood levels, kidney/liver function, complete blood count) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.
MISSED DOSE: It is important to take each dose of this medication as scheduled. If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised September 2023. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
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