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Hospital  >  Departments  >  Laboratory Medicine  >  Lab Test Information Guide  >  Do not take biotin before blood work

No Biotin before blood work

No Biotin before bloodwork

  1. Stop biotin 24 hours before your blood work
  2. Biotin is also called vitamin B7, vitamin H or coenzyme R, commonly foundin hair, skin and nail supplements and multivitamins
  3. Biotin can cause wrong lab test results
  4. Talk to your doctor if you are taking biotin

Biotin can cause wrong lab results

The fact Sheet
Download a printable version: Poster and Information Card

What is Biotin? 

Biotin is one of many B vitamins. It isalso called vitamin B7, vitamin H or coenzyme R

Biotin is found in a wide range of foods,including brewer’s yeast, soybeans,green peas, carrots, cauliflowers, bananas, liver, butter and salmon.

The recommended normal dietary intake is about 30 – 100 mcg (microgram, μg)per day.

High-dose biotin can cause wrong lab test results:

  • High-dose biotin supplements inmilligram (mg) concentrations, such as5 to 10 mg (equivalent to 5,000 to10,000 mcg) are advertised as over-the-counter lifestyle supplement for hair, skin and nail health.
  • These are more than 100 times the recommended normal dietary intake. These types of high-dose biotinsupplements can cause wrong results for certain laboratory tests.
  • you take biotin, please discuss withyour doctor
  • you have taken biotin before the blood work, tell the lab when the last dose was taken and what the dose was

For 24 hours before you have your blood work,
DO NOT take multivitamins or dietary supplements with biotin

References and additional information

Made with Patient and Family Input