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Cycloserine Concentration (Serum/Plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of cycloserine, an antibiotic medication, in your blood. Cycloserine is used to treat certain bacterial infections, including tuberculosis.

Quick summary

["Your doctor may order this test to check if your cycloserine levels are within the safe range while you’re taking this medication."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
23608-3
Short code
cycloSERINE Islt SlowMyco
Synonyms
cycloSERINE Islt SlowMyco
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
method-for-slow-growing-mycobacteria
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your healthcare provider may request this test to monitor your response to cycloserine therapy. It helps ensure the medication is working effectively and to avoid potential side effects by checking if your blood levels are too high or too low.

What Does the Test Involve?

A blood sample is taken from a vein in your arm. The sample is then sent to a lab for analysis using a specialized method to measure cycloserine concentration.

What to Expect Before the Test

No special preparation is needed for this test. You may have some discomfort or bruising at the injection site, but this usually goes away quickly.

What Are Possible Results?

Results will be compared to a reference range specific to cycloserine, though exact values may vary by lab. Your doctor will interpret the results in relation to your medical condition and treatment plan.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Cycloserine Level

Frequently asked questions

What causes cycloserine levels to be checked?
Your doctor may check cycloserine levels if you’re taking this medication to treat tuberculosis or other bacterial infections, or if you have concerns about side effects.
How often are cycloserine levels tested?
The frequency depends on your treatment plan. Some patients may need testing weekly or monthly, especially during the early stages of therapy or if you have certain health conditions.
Can diet or other medications affect cycloserine levels?
Yes, certain foods, supplements, or other medications can interact with cycloserine. Always inform your doctor about all medications, including over-the-counter drugs and herbal products, to avoid unexpected changes in your test results.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy