Skip to content

Fluconazole (Antifungal) Concentration in Serum

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

This test measures the amount of fluconazole, a medication used to treat fungal infections, in your blood serum. It helps doctors monitor your dose and ensure it stays within safe levels.

Quick summary

["This test helps your healthcare provider check if your antifungal medication is working properly and avoid potential side effects."]

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

Key facts at a glance

LOINC
29721-8
Short code
FLUCV Ag Spec Ql IF
Synonyms
FLUCV Ag Spec Ql IF
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
if
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 doctor may order this test if you’re taking fluconazole to treat or prevent fungal infections, such as candidiasis (yeast infections). It’s often done during treatment to adjust your dose based on your blood levels.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm or vein to draw a blood sample. The process takes a few minutes, and you may feel a slight pinch.

What the Test Results Mean

Results are typically reported as a concentration (e.g., micrograms per milliliter). While reference ranges vary by lab, higher-than-normal levels may indicate overdose, and very low levels may mean the medication isn’t working effectively.

Common Reasons for Monitoring

Doctors monitor fluconazole levels to prevent toxicity (e.g., liver damage) and ensure adequate antifungal activity, especially in people with kidney issues or taking other medications that interact with fluconazole.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Fluconazole levels are critical for managing infections like candidiasis in patients on long-term therapy, those with weakened immune systems, or those with kidney problems, as these conditions affect how the drug is processed in the body.

Short name

Fluconazole Level

Frequently asked questions

Why might my fluconazole test be done more often than usual?
If you have kidney problems, take other medications that interact with fluconazole, or are receiving high doses, your doctor may check your levels more frequently to adjust your dose safely.
What if my fluconazole level is too high?
High levels could mean you’re at risk for side effects like nausea, headaches, or liver issues. Your doctor may reduce your dose or switch medications if needed.
Can I eat or drink anything before this test?
You can eat and drink normally before the test, as no special diet is required. However, always follow your doctor’s instructions for any specific preparations.
  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