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Rifabutin Serum Concentration (Quantitative)

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

This test measures the amount of rifabutin, a medication used to treat tuberculosis and certain fungal infections, in your blood.

Quick summary

["Knowing your rifabutin level helps your doctor monitor your dose and ensure it’s working safely."]

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

Key facts at a glance

LOINC
20386-9
Short code
Rifabutin Islt SlowMyco
Synonyms
Rifabutin 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 This Test Is Done

Your doctor may order this test if you’re taking rifabutin to treat an infection. It helps them check if your dose is appropriate and if the drug is staying within safe levels in your bloodstream.

What to Expect Before the Test

No special preparation is needed. You may have a small needle inserted into a vein in your arm, and a blood sample will be drawn. This is usually done in a lab or at a healthcare provider’s office.

What the Results Mean

Results are used to adjust your medication if needed. Low levels may mean your dose isn’t working well, while very high levels could indicate side effects or improper absorption.

Common Side Effects to Watch For

While rare, rifabutin can cause side effects like nausea, stomach pain, or skin rash. If you experience severe reactions (e.g., allergic reactions), seek medical attention immediately.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Rifabutin Level

Frequently asked questions

What does rifabutin do in the body?
Rifabutin belongs to a class of antibiotics that inhibit bacterial RNA synthesis. It’s primarily used to treat infections caused by Mycobacterium tuberculosis or certain fungal pathogens. Monitoring its levels helps prevent toxicity or insufficient treatment.
How often should I get this test?
Your doctor will determine the frequency based on your treatment plan, duration of use, and overall health. Follow their instructions closely—typically, tests may be done weekly or monthly during active treatment.
Can I drink alcohol before this test?
No, avoid alcohol before testing as it may interfere with rifabutin metabolism. Always check with your doctor for specific guidelines tailored to your medication regimen.
  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