Vitamin B6, also referred to as pyridoxine, is a nutrient that the body needs to function correctly. This water-soluble vitamin helps maintain normal nerve function, breaks down proteins, regulates blood sugar levels and makes antibodies, which help fight infections. Foods such as nuts, dried beans, bananas, avocados, bananas, fortified cereals and whole grains contain vitamin B6. Some individuals take supplemental forms of B6 to treat conditions such as high cholesterol, high homocysteine levels and Alzheimer's disease. Medical risks may occur when taking high doses of vitamin B6.
Vitamin B6 Toxicity
The upper intake level for vitamin B6 is 100 mg per day. Some people may take large doses of vitamin B6 to help treat premenstrual syndrome or carpal tunnel syndrome, although the efficacy is unknown. Taking over 500 mg per day is a mega dose, according to the Merck Manuals of Medical Information. The larger dose you take, the more likely adverse reactions may occur, but some side effects may occur in doses lower than 500 mg per day. Stopping the supplementation will help decrease the toxic effects of the toxic levels, but some symptoms may become permanent.
Brain and Nerve Problems
Taking high doses of vitamin B6 for a long time may increase the risk of developing problems with the brain or nervous system. Peripheral neuropathy may occur and cause decreased sensation in the hands and feet. The neuropathy may also cause a tight feeling in the hands or feet as well as burning pain, numbness and tingling. Severe impairment may occur in sensing the position of the arms and legs in relation to the body and difficulty feeling vibrations. Walking may become a problem. Difficulty walking may continue after you stop taking supplemental vitamin B6. An overdose of vitamin B6 can cause seizures.
Additional Possible Side Effects
Normal dosages of vitamin B6 don't normally cause adverse reactions and reactions that occur are usually mild. Additional side effects from taking vitamin B6 include gastrointestinal symptoms such as an upset stomach. Some individuals may develop a headache when taking supplemental vitamin B6. The vitamin may also cause side effects such as depression, confusion, irritability and sores on the tongue and mouth.
Allergic Reactions
Some people taking vitamin B6 may experience an allergic reaction. Signs and symptoms of an allergic reaction include difficulty breathing, increased heart rate, skin hives and swelling of the airway, which may include the throat, mouth, tongue, lips or face. An allergic reaction signifies a medical emergency and the condition requires immediate attention to prevent possible complications or death.
References
- The Merck Manual; B6; Larry E. Johnson, MD, PhD; April 2007
- MedlinePlus; Vitamin B6; Alison Evert, MS, RD, CDE; February 2011
- MedlinePlus; Pyridoxine; September 2008
- Merck Manual Home Health Handbook; Vitamin B6; Larry E. Johnson, MD, PhD; August 2007
- Drugs.com; Pyridoxine; July 2011
- Office of Dietary Supplements: Vitamin B6
