Pyridoxine is a water-soluble vitamin which functions in the metabolism of carbohydrates, proteins and fats. It is essential in Hb formation and GABA synthesis within the CNS. It also aids in the release of glycogen stored in the liver and muscles.

Pyridoxine (vitamin B6) is used to prevent or treat low levels of vitamin B6 in people who do not get enough of the vitamin from their diets. Most people who eat a normal diet do not need extra vitamin B6. However, some conditions (such as alcoholism, liver disease, overactive thyroid, heart failure) or medications (such as isoniazid, cycloserine, hydralazine, penicillamine) can cause low levels of vitamin B6. Vitamin B6 plays an important role in the body. It is needed to maintain the health of nerves, skin, and red blood cells.

Pyridoxine has been used to prevent or treat a certain nerve disorder (peripheral neuropathy) caused by certain medications (such as isoniazid). It has also been used to treat certain hereditary disorders (such as xanthurenic aciduria, hyperoxaluria, homocystinuria).

ADULTS:

BY MOUTH:

• For hereditary sideroblastic anemia: Initially, 200-600 mg of vitamin B6 is used. The dose is decreased to 30-50 mg per day after an adequate response.
• For vitamin B6 deficiency: In most adults, the typical dose is 2.5-25 mg daily for three weeks then 1.5-2.5 mg per day thereafter. In women taking birth control pills, the dose is 25-30 mg per day.
• For abnormally high levels of homocysteine in the blood: For reducing high levels of homocysteine in the blood after childbirth, 50-200 mg of vitamin B6 has been taken alone. Also, 100 mg of vitamin B6 has been taken in combination with 0.5 mg of folic acid.
• For preventing macular degeneration: 50 mg of vitamin B6 in the form of pyridoxine has been used daily in combination with 1000 mcg of vitamin B12 (cyanocobalamin) 1000 mcg and 2500 mcg of folic acid for about 7 years.
• For hardening of the arteries (atherosclerosis): A specific supplement (Kyolic, Total Heart Health, Formula 108, Wakunga) containing 250 mg of aged garlic extract, 100 mcg of vitamin B12, 300 mcg of folic acid, 12.5 mg of vitamin B6, and 100 mg of L-arginine daily for 12 months.
• For kidney stones: 25-500 mg of vitamin B6 has been used daily.
• For nausea during pregnancy: 10-25 mg of vitamin B6 taken three or four times per day has been used. In people who don't respond to vitamin B6 alone, a combination product containing vitamin B6 and the drug doxylamine (Diclectin, Duchesnay Inc.) is used three or four times per day. Also, another product containing 75 mg of vitamin B6, 12 mcg of vitamin B12, 1 mg of folic acid, and 200 mg of calcium (PremesisRx, KV Pharmaceuticals) is used daily.
• For symptoms of premenstrual syndrome (PMS): 50-100 mg of vitamin B6 is used daily, alone or along with 200 mg of magnesium.
• For treating tardive dyskinesia: 100 mg of vitamin B6 per day has been increased weekly up to 400 mg per day, given in two divided doses.

INJECTED INTO THE MUSCLE:

• Hereditary sideroblastic anemia: 250 mg of vitamin B6 daily, reduced to 250 mg of vitamin B6 weekly once adequate response is achieved.

CHILDREN:

BY MOUTH:

• For kidney stones: Up to 20 mg/kg daily in children aged 5 years and up.

INJECTED INTO THE VEIN OR MUSCLE:

• For seizures that respond to vitamin B6 (pyridoxine-dependent seizures): 10-100 mg is recommended.

The daily recommended dietary allowances (RDAs) of vitamin B6 are:

• Infants 0-6 months, 0.1 mg
• Infants 7-12 months, 0.3 mg
• Children 1-3 years, 0.5 mg
• Children 4-8 years, 0.6 mg
• Children 9-13 years, 1 mg
• Males 14-50 years, 1.3 mg
• Males over 50 years, 1.7 mg
• Females 14-18 years, 1.2 mg
• Females 19-50 years, 1.3 mg
• Females over 50 years, 1.5 mg
• Pregnant women, 1.9 mg
• Breast-feeding women, 2 mg
• Some researchers think the RDA for women 19-50 years should be increased to 1.5-1.7 mg per day. 

The recommended maximum daily intake is:

• Children 1-3 years, 30 mg
• Children 4-8 years, 40 mg
• Children 9-13 years, 60 mg

Adults, pregnant and breast-feeding women:

• 14-18 years, 80 mg
• over 18 years, 100 mg

Pyridoxine usually has no side effects when used in recommended doses.

If your doctor has prescribed this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Pyridoxine can cause side effects when taken in large doses for a long time. Tell your doctor right away if any of these unlikely but serious side effects occur: headache, nausea, drowsiness, numbness/tingling of arms/legs.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

Before taking pyridoxine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

During pregnancy, this vitamin has been found to be safe when used in recommended doses.

This vitamin passes into breast milk and is considered to be safe during breast-feeding when used in recommended doses. Consult your doctor for more information.

Pregnancy & Lactation

Category A: Controlled studies in women fail to demonstrate a risk to the foetus in the 1st trimester (and there is no evidence of a risk in later trimesters), and the possibility of foetal harm remains remote.