Drug information of Vitamin B6
Vitamin B6 is a water-soluble vitamin. Water-soluble vitamins dissolve in water so the body cannot store them. Leftover amounts of the vitamin leave the body through the urine. That means you need a regular supply of these vitamins in your diet.
Pyridoxine can be found in certain foods such as cereals, beans, vegetables, liver, meat, and eggs. It can also be made in a laboratory.
Vitamin B6 helps the body to:
- Make antibodies. Antibodies are needed to fight many diseases.
- Maintain normal nerve function.
- Make hemoglobin. Hemoglobin carries oxygen in the red blood cells to the tissues. A vitamin B6 deficiency can cause a form of anemia.
- Break down proteins. The more protein you eat, the more vitamin B6 you need.
- Keep blood sugar (glucose) in normal ranges.
The total adult body pool consists of 16 to 25 mg of pyridoxine. Its half-life appears to be 15 to 20 days. Vitamin B6 is degraded to 4-pyridoxic acid in the liver. This metabolite is excreted in the urine.
The need for pyridoxine increases with the amount of protein in the diet. The tryptophan load test appears to uncover early vitamin B6 deficiency by detecting xanthinurea. The average adult minimum daily requirement is about 1.25 mg. The ‘‘Recommended Dietary Allowance’’ of the National Academy of Sciences is estimated to be as much as 2.2 mg for adults and 2.5 mg for pregnant and lactating women. The requirements are more in persons having certain genetic defects or those being treated with isonicotinic acid hydrazide (INHJ) or oral contraceptives.
Drug indicationsanemia , nausea , vomiting , Seizures , Nutritional supplement
Usual Adult Dose for Drug Induced Vitamin/Mineral Deficiency
Drug Induced Neuritis:
Cycloserine: 100 to 300 mg/day orally in divided doses.
Isoniazid or penicillamine: 100 to 200 mg/day orally for 3 weeks or 25 to 100 mg/day for prophylaxis.
Oral contraceptives: 25 to 30 mg/day orally.
Hydralazine: 25 mg/kg. One-third of the dose should be administered IM and the remainder administered as an IV infusion over 3 hours.
Isoniazid: 1 to 4 grams IV as a first dose, then 1 g IM every 30 minutes until the total required dose has been administered (given with other anticonvulsants as needed). The total dose administered should equal the amount of isoniazid ingested.
Mushroom ingestion (genus Gyromitra): 25 mg/kg IV infused over 15 to 30 minutes. Repeat as needed to a maximum total daily dose of 15 to 20 g.
Usual Adult Dose for Dietary Supplement
10 to 25 mg/day orally, IM, or IV for 3 weeks followed by 2 to 5 mg/day from a multivitamin product.
Usual Adult Dose for Anemia
Sideroblastic, hereditary: 200 to 600 mg orally daily. If adequate response obtained, dose may be decreased to 30 to 50 mg orally daily.
If therapeutic response is not obtained after 1 to 2 months of pyridoxine therapy, a different therapy should be considered.
Nausea and vomiting of Pregnancy:
25 mg orally every 8 hours.
Usual Pediatric Dose for Drug Induced Vitamin/Mineral Deficiency
Drug Induced Neuritis (cycloserine, isoniazid, hydralazine, penicillamine) :
Treatment: 10 to 50 mg/day.
Prophylaxis: 1 to 2 mg/kg/day
Hydralazine: 25 mg/kg: One-third of the dose should be administered IM and the remainder administered as an IV infusion over 3 hours.
Isoniazid: Acute ingestion of known amount: Initial: A total dose of pyridoxine equal to the amount of isoniazid ingested (maximum dose: 70 mg/kg, up to 5 g); administer at a rate of 0.5 to 1 g/minute until seizures stop or the maximum initial dose has been administered; may repeat every 5 to 10 minutes as needed to control persistent seizure activity and/or CNS toxicity. If seizures stop prior to the administration of the calculated initial dose, infuse the remaining pyridoxine over 4 to 6 hours. Acute ingestion of unknown amount: Initial: 70 mg/kg (maximum dose: 5 g); administer at a rate of 0.5 to 1 g/minute; may repeat every 5 to 10 minutes as needed to control persistent seizure activity and/or CNS toxicity.
Mushroom ingestion (genus Gyromitra): 25 mg/kg IV. Repeat as needed up to a maximum total dose of 15 to 20 g.
Usual Pediatric Dose for Dietary Supplement
5 to 25 mg/day orally, IM, or IV for 3 weeks followed by 1.5 to 2.5 mg/day from a multivitamin product.
Usual Pediatric Dose for Seizures
10 to 100 mg PO, IM, or IV initially, followed by 2 to 100 mg orally daily.
Side effectsdifficulty urinating
InteractionsLevodopa , Alpha-Lipoic Acid
- Single deficiency, as of pyridoxine alone, is rare. Multiple vitamin deficiency is to be expected in any inadequate diet. Patients treated with levodopa should avoid supplemental vitamins that contain more than 5 mg pyridoxine in the daily dose.
- Women taking oral contraceptives may exhibit increased pyridoxine requirements.
- To make sure you can safely receive injectable Vitamin B6, tell your doctor if you have heart disease or kidney disease.
- Ask a doctor before using this medicine if you are pregnant or breast-feeding. Your dose needs may be different. High doses of Vitamin B6 can harm a nursing baby.
- Do not give this medicine to a child without medical advice.
Points of recommendation
- Vitamin B6 tablets are taken by mouth. Injectable this medicine is injected into a muscle or into a vein through an IV. You may be shown how to use injections at home. Do not give yourself this medicine if you do not understand how to use the injection and properly dispose of needles, IV tubing, and other items used.
- The recommended dietary allowance of Vitamin B6 increases with age. Follow your healthcare provider's instructions. You may also consult the Office of Dietary Supplements of the National Institutes of Health, or the U.S. Department of Agriculture (USDA) Nutrient Database (formerly "Recommended Daily Allowances") listings for more information.
- Vitamin B6 may be only part of a complete program of treatment that also includes a special diet. Follow the diet plan created for you by your doctor or nutrition counselor. Get familiar with the list of foods you should eat or avoid to help control your condition.
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