Pyridoxalphosphate (Tablets) Instructions for Use

ATC Code

A11HA06 (Pyridoxalphosphate)

Active Substance

Pyridoxal phosphate (BP British Pharmacopoeia)

Clinical-Pharmacological Group

Vitamin preparation

Pharmacotherapeutic Group

Metabolic agent

Indications

• Treatment and prevention of vitamin B6 deficiency states associated with inadequate dietary intake, malabsorption syndromes, or conditions of increased metabolic demand.
• As part of complex therapy for neurological disorders, including peripheral neuropathies (such as diabetic neuropathy), radiculitis, neuralgia, and seizures in infants that are pyridoxine-dependent.
• Supportive therapy in various dermatological conditions like seborrheic-like dermatitis, exfoliative dermatitis, and cheilosis.
• Adjunctive treatment for certain hematological disorders, particularly sideroblastic anemia, where it may help to correct the underlying metabolic abnormality.
• Management of nausea and vomiting during pregnancy (morning sickness) when other interventions have proven ineffective or are not suitable.
• Correction of metabolic imbalances that may occur during therapy with certain drugs, such as isoniazid or cycloserine, which can act as pyridoxine antagonists.

Contraindications

• Hypersensitivity to pyridoxal phosphate or any of the excipients listed in the formulation, such as lactose or quinoline yellow. A detailed composition is provided in the ‘Dosage forms’ tab.
• Patients with a history of severe allergic reactions to other vitamin B6 preparations or components of the film coating.
• Use with caution in patients with Parkinson’s disease who are undergoing treatment with levodopa without a concomitant decarboxylase inhibitor, as pyridoxine can accelerate the peripheral metabolism of levodopa, thereby reducing its clinical efficacy.
• This product contains lactose. Patients with rare hereditary problems of galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption should not take this medicine.

Dosage Regimen

The dosage must be individualized based on the specific condition being treated, its severity, and the patient’s response. The following are general guidelines; the prescribing physician’s instructions must always be followed.

For adults and children over 12 years of age: The typical therapeutic dose ranges from 10 mg to 50 mg per day, administered in 1 to 3 divided doses. For the prevention of deficiency, a dose of 10-20 mg per day is often sufficient. For the treatment of established deficiency or specific medical conditions like neuropathy or sideroblastic anemia, higher doses in the range of 30-50 mg daily are commonly used.

For the management of drug-induced neuropathy (e.g., from isoniazid), the dosage may be increased to 50 mg to 200 mg daily, administered under strict medical supervision. The duration of therapy is determined by the underlying cause of the deficiency or the duration of the provoking drug therapy.

The tablets should be swallowed whole with a sufficient amount of water, with or after a meal to minimize potential gastrointestinal discomfort. Do not crush or chew the film-coated tablets.

Adverse Reactions

Pyridoxal phosphate is generally well-tolerated at recommended dosages. However, like all medicines, it can cause side effects, although not everybody gets them.

At high doses (exceeding 200 mg per day for extended periods), sensory neuropathy is the most serious adverse reaction. This may manifest as numbness, tingling, or a “pins and needles” sensation in the hands and feet, instability when walking (ataxia), and decreased sensation to touch, temperature, and vibration. These neurological effects may be irreversible even after discontinuation of the vitamin.

Gastrointestinal disturbances such as nausea, vomiting, epigastric pain, heartburn, and loss of appetite have been reported, though they are uncommon at standard doses.

Allergic reactions are rare but can occur. Signs may include skin rash, itching (pruritus), urticaria (hives), and in very rare instances, anaphylaxis. Discontinue use immediately and seek medical attention if any signs of a severe allergic reaction appear.

Other rarely reported effects include headache, drowsiness, and a decrease in serum folic acid concentrations. If any adverse reaction becomes severe or persistent, or if you notice any side effects not listed here, consult your doctor or pharmacist.

Drug Interactions

Concomitant use of Pyridoxalphosphate with other medicines should be done under medical supervision. Inform your healthcare provider about all the products you are using, including prescription, over-the-counter, and herbal products.

Levodopa: Pyridoxine can reverse the antiparkinsonian effects of levodopa by enhancing its peripheral decarboxylation. This interaction is not significant when levodopa is administered in combination with a peripheral decarboxylase inhibitor (e.g., carbidopa, as in Sinemet).

Isoniazid, Cycloserine, and Penicillamine: These drugs are pyridoxine antagonists and can increase the requirement for vitamin B6, potentially leading to deficiency symptoms such as neuropathy. Conversely, pyridoxine supplementation is often required to prevent these adverse effects during long-term therapy with these agents.

Phenobarbital and Phenytoin: There is some evidence that high doses of pyridoxine may decrease serum concentrations of these antiepileptic drugs, potentially reducing their seizure-control efficacy. Serum level monitoring of these anticonvulsants may be advisable.

Altretamine and certain chemotherapeutic agents: Pyridoxine is sometimes used to mitigate the neurotoxicity associated with these drugs, but the interaction is complex and should be managed by an oncologist.

Overdose

Acute overdose with Pyridoxalphosphate is unlikely to cause serious harm due to the water-soluble nature of the vitamin. Single doses of several grams have been reported without life-threatening effects. However, chronic ingestion of very high doses (typically >1 gram per day for months or years) can lead to severe sensory neuropathy, as described in the ‘Adverse Reactions’ section.

Symptoms of acute overdose may include intensified adverse effects, such as severe nausea, headache, and fatigue.

There is no specific antidote for pyridoxine overdose. Treatment is supportive and symptomatic. In case of suspected overdose, discontinue the medication immediately and consult a doctor or poison control center. Gastric lavage or administration of activated charcoal may be considered if the overdose is very recent. Adequate hydration should be maintained.

It is critically important to adhere to the prescribed dosage and not to self-medicate with high-dose vitamin B6 supplements without medical supervision.

Storage Conditions

Store at 2°C (36°F) to 25°C (77°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.