Vitamin B6 (pyridoxine) deficiency is uncommon in the US since most people get adequate amounts from food. When deficiency does occur, it's usually mild and tied to specific medical conditions, kidney problems, or certain medications. Severe deficiency can cause anemia, seizures, and dermatitis.
Common symptoms
Microcytic, hypochromic anemia (different from B12/folate-related anemia)
Skin disorders — seborrheic dermatitis around eyes, nose, and mouth
Cracks at the corners of the mouth, swollen tongue
Depression, confusion, irritability
Weakened immune function, frequent infections
Tingling or numbness in hands and feet
Seizures (rare, severe deficiency or pyridoxine-dependent epilepsy in infants)
Symptoms often overlap with other B-vitamin deficiencies
At-risk groups
People with kidney disease, especially on dialysis or post-kidney transplant
People with autoimmune conditions (rheumatoid arthritis, celiac, Crohn's, ulcerative colitis)
People with alcohol use disorder
Long-term users of certain medications (isoniazid, hydralazine, penicillamine, levodopa, anticonvulsants)
Older adults with poor diet
Pregnant women (B6 needs increase)
People with rare genetic disorders affecting B6 metabolism
When to see a doctorPersistent skin issues around the face, unexplained microcytic anemia (especially when iron levels are normal), or peripheral neuropathy in any at-risk group warrants evaluation. Important warning: long-term high-dose B6 supplementation (>100-200 mg/day) can itself cause sensory neuropathy — never exceed the UL without medical supervision.