Pyridoxine Hydrochloride

• Approved Indications:
• Treatment and prevention of Vitamin B6 deficiency due to poor dietary intake, malabsorption, or increased physiological demands.
• Management of pyridoxine-dependent seizures in neonates and infants.
• Adjunct therapy for prevention and treatment of peripheral neuropathy caused by isoniazid, hydralazine, or penicillamine therapy.
• Treatment of sideroblastic anemia.
• Relief of symptoms associated with pyridoxine deficiency neuropathy.
• Off-label/Clinically Accepted Uses:
• Management of premenstrual syndrome (PMS) symptoms.
• Adjunct treatment in homocystinuria.
• Supportive therapy to reduce neurotoxicity from certain medications like cycloserine or levodopa.

• Adults:
• Prevention of deficiency: 1.3–2 mg daily (RDA).
• Therapeutic doses: 10–50 mg daily orally, depending on condition severity.
• For sideroblastic anemia or neuropathy: up to 100 mg daily in divided doses.
• Pediatrics:
• RDA varies by age (0.5–1.3 mg daily).
• For seizures: up to 30 mg/kg/day orally in divided doses under specialist supervision.
• Special Populations:
• Pregnancy and lactation: up to 2 mg daily as per RDA; higher doses only with medical advice.
• Hepatic or renal impairment: no specific dose adjustment, but monitor carefully.
• Route:
• Oral tablets, capsules, or parenteral injection (IM or IV for severe deficiency).
• Frequency:
• Once or multiple times daily depending on dosage and indication.

Pyridoxine hydrochloride is converted in the body to pyridoxal 5’-phosphate, the active coenzyme form of vitamin B6. It functions as a cofactor in numerous enzymatic reactions involved in amino acid metabolism, neurotransmitter synthesis (e.g., serotonin, dopamine, GABA), hemoglobin synthesis, and lipid metabolism. This coenzyme activity is essential for normal nervous system function, red blood cell production, and homocysteine regulation, which collectively contribute to the therapeutic effects.

• Absorption: Well absorbed orally from the gastrointestinal tract.
• Distribution: Widely distributed in tissues including liver, muscle, and brain.
• Metabolism: Converted mainly in the liver to active pyridoxal 5’-phosphate.
• Excretion: Excreted primarily in urine as pyridoxic acid.
• Half-life: Approximately 15 to 20 days depending on body stores.
• Onset of Action: Therapeutic effects develop within days to weeks.

• Pregnancy: FDA Category A; no evidence of risk in humans when used at recommended doses.
• Lactation: Safe during breastfeeding; low levels excreted in breast milk with no known adverse effects on the infant.

• Vitamin supplement
• Water-soluble vitamin (Vitamin B6)

• Hypersensitivity to pyridoxine hydrochloride or formulation excipients.
• Caution in patients with hereditary optic neuropathies (e.g., Leber’s disease).

• Avoid chronic high-dose therapy (>200 mg/day) to prevent sensory neuropathy.
• Monitor patients for signs of neurotoxicity, especially with prolonged use.
• Use with caution in patients with pre-existing neuropathy.
• Discontinue immediately if symptoms of neuropathy appear or worsen.
• Not a substitute for treatment of underlying causes of deficiency.

• Common:
• Mild gastrointestinal discomfort (nausea, heartburn).
• Serious (rare):
• Sensory neuropathy with prolonged high doses.
• Hypersensitivity reactions (rash, photosensitivity, anaphylaxis).
• Side effects are usually dose-dependent and reversible upon discontinuation.

• Isoniazid, hydralazine, penicillamine: Increase requirement for pyridoxine to prevent neuropathy.
• Levodopa: May reduce levodopa efficacy unless administered with carbidopa.
• No significant interactions involving CYP450 enzymes or food.

• Continued endorsement by WHO and other health authorities for vitamin B6 deficiency treatment and prevention.
• Emphasis on avoiding excessive doses due to neuropathy risk.
• No recent major changes in labeling or dosing recommendations.

• Store at controlled room temperature between 20°C and 25°C (68°F to 77°F).
• Protect from moisture, heat, and light.
• Keep containers tightly closed and out of reach of children.