Skip to content

Vitamin A (Retinol) in Serum or Plasma by Immunoassay

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

This test measures the amount of vitamin A, an essential nutrient important for vision, immune function, and skin health, in your blood.

Quick summary

["Checks if you have enough vitamin A for good health."]

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

Key facts at a glance

LOINC
30075-6
Short code
RSV A RNA Spec Ql NAA+probe
Synonyms
RSV A RNA Spec Ql NAA+probe
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
probe-amp-tar
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 have symptoms like night blindness, frequent infections, dry skin, or poor wound healing. It can also be used to monitor vitamin A levels in people with certain medical conditions, like liver disease or malabsorption disorders, or those taking supplements.

What to Expect Before the Test

No special preparation is needed. You may have a small needle inserted into a vein in your arm to draw blood. If you’re concerned about needles, let your healthcare provider know. Avoid alcohol before the test if possible.

What Happens During the Test?

A healthcare professional will clean the area, insert a needle into your vein, and collect a blood sample. The process usually takes a few minutes. The sample is then sent to a lab for analysis.

What Are Possible Results?

Results are compared to a general range of healthy vitamin A levels, but exact numbers can vary by lab. Low levels may indicate vitamin A deficiency, while very high levels could suggest overconsumption or certain medical conditions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Vitamin A Level

Frequently asked questions

What Does This Test Tell Your Doctor?
Your doctor may use these results to diagnose vitamin A deficiency, assess liver function, or monitor treatment for conditions like cystic fibrosis or malnutrition. High levels might prompt further investigation into possible causes like liver disease or excessive vitamin A intake.
How Often Should I Get This Test?
Your doctor will determine the frequency based on your health needs. For example, people with liver disease or those taking high-dose supplements may need regular monitoring. Pregnant women or those with specific dietary concerns might also need periodic checks.
What If My Results Are Out of Range?
If your results are low, your doctor may recommend dietary changes, supplements, or further testing to identify the cause. If high, they may investigate potential causes like liver issues or medication interactions. Follow your doctor’s advice for next steps.
  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