Pyridoxine

Pyridoxine is not naturally synthesized in humans and must be obtained through diet. It is used as a supplement to treat nausea and vomiting in pregnancy and to prevent or reduce nerve damage caused by isoniazid, a drug used to treat tuberculosis, and certain toxins.

Pyridoxine is essential for maintaining the health and function of nerves, muscles, skin, and the immune system. It is converted to its active form, pyridoxal 5-phosphate, in the body. This coenzyme is involved in the metabolism of proteins, carbohydrates, and fats, as well as the release of stored glycogen in the liver and muscles. Pyridoxine also plays a role in the synthesis of DNA, RNA, neurotransmitters, amino acids, and heme, which carries oxygen in red blood cells.

Pyridoxine can be found in foods such as chickpeas, fish, beef liver, poultry, and various vegetables, seeds, and fruits (excluding citrus). Deficiency of pyridoxine can lead to nerve damage, confusion, insomnia, and dermatitis. Most people can obtain sufficient pyridoxine through their diet.

Pyridoxine is available by prescription or over-the-counter as a supplement. It is used to treat pyridoxine deficiency, nausea and vomiting in pregnancy, peripheral neuropathy associated with isoniazid therapy, and various types of toxicity.

• Pyridoxine deficiency
• Nausea and vomiting of pregnancy
• Prevention of peripheral neuropathy associated with isoniazid therapy for tuberculosis
• Prevention and treatment of neurological toxicities including seizures or coma caused by isoniazid overdose
• Ethylene glycol poisoning
• Treatment and prevention of gyromitrin-containing mushroom (false morel) overdose or toxicity
• Hydrazine toxicity

Warnings

• Do not take pyridoxine if you are hypersensitive to it or any components in the formulation.
• Taking large doses of pyridoxine for prolonged periods can cause severe and permanent neuropathies.
• Some intravenous formulations of pyridoxine may contain aluminum. Use caution in premature newborns and patients with impaired kidney function.
• Doses higher than 200 mg may result in dependence and withdrawal.
• When treating pyridoxine deficiency, evaluate patients for other vitamin deficiencies.

Side effects of pyridoxine

Common side effects of pyridoxine include:

• Headache
• Drowsiness
• Abnormal skin sensations
• Nerve damage
• Impaired coordination, balance, and speech
• Seizure (with high IV doses)
• Folate deficiency
• Excessive acidity in body fluids
• Increase in liver enzyme AST
• Nausea
• Hypersensitivity reaction

This is not an exhaustive list of side effects. Contact your doctor for medical advice on serious side effects or adverse reactions. Report side effects or health problems to the FDA at 1-800-FDA-1088.

Pyridoxine dosages

Tablets

Tablets, Extended Release

Capsule

Adult:

Recommended Daily Allowance (RDA)

• Younger than 50 years old: 1.3 mg/day
• Older than 50 years old: 1.7 mg/day
• Younger than 50 years old: 1.3 mg/day
• Older than 50 years old: 1.5 mg/day
• Pregnant: 1.9 mg/day
• Lactation: 2 mg

Pyridoxine Deficiency

• 10-20 mg/day intravenous/intramuscular (IV/IM) for 3 weeks
• 2.5-10 mg/day oral

Nausea and Vomiting in Pregnancy

• 10-25 mg orally every 8 hours

Prevention of Peripheral Neuropathy

• Patients treated with isoniazid for tuberculosis: 25-50 mg/day oral

Pediatric:

RDA

• Children younger than 6 months: 0.1 mg/day
• Children 6-12 months: 0.3 mg/day
• Children 1-3 years: 0.5 mg/day
• Children 3-8 years: 0.6 mg/day
• Children 8-13 years: 1 mg/day
• Children 13-18 years: 1.3 mg/day (male); 1.5 mg/day (female)

Isoniazid-Induced Seizures/Coma

• Dose of pyridoxine is equal to amount of isoniazid ingested
• Administer at rate of 0.5-1 g/min until seizures stop or maximum initial dose (70 mg/kg) administered; may administer every 5-10 minutes as needed to control persistent seizure activity and/or CNS toxicity

Overdose

• Pyridoxine overdose can cause neurological symptoms such as tingling, numbness, difficulty walking, and coordination problems. There is no specific antidote for pyridoxine toxicity.
• Treatment involves discontinuing pyridoxine supplementation and providing symptomatic and supportive care, including physical therapy, until symptoms improve.

Drug interactions

Inform your doctor of all medications you are taking to avoid potential interactions. Do not start, discontinue, or change the dosage of any medication without your doctor’s recommendation.

• Pyridoxine has no known severe interactions with other drugs.
• Serious interactions include:

• selinexor
• azithromycin
• cisplatin
• clarithromycin
• dichlorphenamide
• erythromycin base
• erythromycin ethylsuccinate
• erythromycin lactobionate
• erythromycin stearate
• levodopa
• omadacycline
• roxithromycin

This is not an exhaustive list of drug interactions. For more information, use the RxList Drug Interaction Checker.

Always inform your doctor or healthcare provider about all prescription and over-the-counter medications you are using. Keep a list of the medication information. If you have any questions, consult your doctor or healthcare provider.

Pregnancy and breastfeeding

• Pyridoxine is an essential micronutrient, and its requirement may increase during pregnancy.
• Pyridoxine is recommended for the treatment of nausea and vomiting in pregnancy.
• Studies show no evidence of fetal harm from pyridoxine use in pregnancy and it may offer protection from congenital cardiovascular malformations.
• Pyridoxine use in pregnancy is generally safe in recommended doses.
• Pyridoxine is present in breast milk and benefits breastfeeding babies. It is safe for nursing mothers to take pyridoxine in recommended doses.

Additional information

• Do not take supplemental pyridoxine unless deficient or with specific requirements. Obtain pyridoxine through foods rich in it.
• Do not exceed the recommended daily dose of over-the-counter pyridoxine supplements.
• If overdose occurs, discontinue pyridoxine and seek medical help or contact Poison Control.
• Pyridoxine is sold as a dietary supplement and is not tightly regulated by the FDA. Be cautious and choose products from reputable manufacturers.

Summary

Pyridoxine, a form of vitamin B6, is a water-soluble micronutrient essential for the normal functioning of various biological systems in the body. Common side effects of pyridoxine include headache, drowsiness, abnormal skin sensations, nerve damage, impaired coordination, seizure, folate deficiency, excessive acidity in body fluids, increase in liver enzyme AST, nausea, and hypersensitivity reaction.