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.

Vitamin B6 (pyridoxine) is essential for the processing (metabolism) of carbohydrates, amino acids, and fats (lipids), as well as for normal nerve function and for the formation of red blood cells. It also helps keep the skin healthy. (See also Overview of Vitamins.)
Good sources of vitamin B6 include dried yeast, liver, other organ meats, whole-grain cereals, fish, and legumes.