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Vitamin B6 Deficiency

By

Larry E. Johnson

, MD, PhD, University of Arkansas for Medical Sciences

Last full review/revision Nov 2020
CLICK HERE FOR THE PROFESSIONAL VERSION

Vitamin B6 is in most foods, but people can have vitamin B6 deficiency if they do not absorb it properly.

  • Many foods contain vitamin B6, but extensive processing can remove the vitamin.

  • People may have seizures, a scaly rash, a red tongue, cracks in the corners of the mouth, or a pins-and-needles sensation in the hands and feet.

  • The diagnosis is based on symptoms, the presence of possible causes, and response to vitamin B6 supplements.

  • Vitamin B6 supplements, taken by mouth, can correct the deficiency.

Good sources of vitamin B6 include dried yeast, liver, other organ meats, whole-grain cereals, fish, and legumes.

Causes of Vitamin B6 Deficiency

Because vitamin B6 is present in many foods, the deficiency rarely results from inadequate intake except in severe malnutrition. However, deficiency can also occur, because extensive processing can remove vitamin B6 from foods.

Vitamin B6 deficiency often results from

These drugs include antiseizure drugs Antiseizure drugs In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more , the antibiotic isoniazid (used for tuberculosis), hydralazine (used to treat high blood pressure), corticosteroids Corticosteroids: Uses and Side Effects Corticosteroids: Uses and Side Effects , and penicillamine (used to treat such disorders as rheumatoid arthritis and Wilson disease).

Symptoms of Vitamin B6 Deficiency

In adults, vitamin B6 deficiency can cause inflammation of the skin (dermatitis) and a red, greasy, scaly rash. The hands and feet may feel numb and prickling—like pins and needles. The tongue may become sore and red, and cracks may form in the corners of the mouth. People may become confused, irritable, and depressed. They may have seizures.

Rarely, vitamin B6 deficiency causes seizures in infants. Antiseizure drugs may be ineffective in treating these seizures in infants.

Diagnosis of Vitamin B6 Deficiency

  • History and physical examination

  • Response to vitamin B6 supplements

The diagnosis of vitamin B6 deficiency is based on symptoms, the presence of conditions that can cause the deficiency, and response to vitamin B6 supplements.

Blood tests may be done, but no routine blood test can clearly confirm the diagnosis.

Treatment of Vitamin B6 Deficiency

  • Correction of the cause

  • Vitamin B6 supplements

Causes of vitamin B6 deficiency are corrected when possible.

If people have the deficiency or if they are taking a drug that depletes vitamin B6 in the body, they should take vitamin B6 supplements by mouth. Taking vitamin B6 supplements usually corrects the deficiency in adults.

Drugs Mentioned In This Article

Generic Name Select Brand Names
LANIAZID
No US brand name
CUPRIMINE
NOTE: This is the Consumer Version. DOCTORS: CLICK HERE FOR THE PROFESSIONAL VERSION
CLICK HERE FOR THE PROFESSIONAL VERSION
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