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Rifampin Quantitative Serum Concentration Measurement

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

This test measures the amount of rifampin, a medication used to treat certain bacterial infections, in your blood serum. It helps doctors monitor how well your body is processing the drug.

Quick summary

["This test ensures your rifampin dose is safe and effective for your treatment."]

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

Key facts at a glance

LOINC
73167-9
Short code
rifAMPin ind plt IgM SerPl Ql FC
Synonyms
rifAMPin ind plt IgM SerPl Ql FC
Category
hematology
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
flow-cytometry
CPT
82784
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 healthcare provider may order this test if you’re taking rifampin to treat conditions like tuberculosis, meningitis, or other serious infections. It helps adjust your medication dose to avoid side effects or reduce the risk of resistance.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm to draw a blood sample. The process is quick and usually painless. If you’re on blood thinners or have a history of bleeding issues, let your doctor know.

What the Test Results Mean

Results are used to check if your rifampin levels are within the target range for your condition. Too high or too low levels can affect how well the drug works or cause side effects. Your doctor will discuss the results with you.

Possible Side Effects or Risks

Rifampin can cause mild side effects like nausea, stomach upset, or rash. Rarely, it may affect liver function or cause allergic reactions. If you experience severe symptoms like yellowing of skin/eyes, dark urine, or swelling, contact your doctor immediately.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Monitoring rifampin levels is critical because this medication can be toxic at high doses and may not work effectively if levels are too low. Proper dosing helps prevent drug resistance and reduces side effects, ensuring the best possible treatment outcome.

Short name

Rifampin Level

Frequently asked questions

How often will I need this test?
Your doctor will determine the frequency based on your treatment plan, how long you’ve been taking rifampin, and your overall health. Typically, tests are done during the early stages of treatment and then periodically to adjust doses if needed.
What if my results are outside the expected range?
If your rifampin level is too high, your doctor may reduce your dose or switch to a different medication. If it’s too low, they might increase your dose or check for interactions with other drugs you’re taking. Always follow your healthcare provider’s instructions.
Can I eat or drink before the blood test?
You can eat and drink normally before the test, as it doesn’t require fasting. However, inform your doctor about any medications or supplements you’re taking, as they may affect the 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