(1991; 44 pages) [French] [Spanish]
Tablet 10 mg (hydrochloride)
Pyridoxine is the naturally occurring form of vitamin B6. Following absorption from the gastrointestinal tract, it is converted in the liver to a coenzyme, pyridoxal phosphate, that is involved in many metabolic processes. Isoniazid interferes competitively with pyridoxine metabolism by inhibiting the formation of the active form of the vitamin, and hence often results in peripheral neuropathy.
To prevent the development of peripheral neuropathy in patients receiving isoniazid.
Dosage and administration
Adults and children: 10 mg daily suffices for prophylaxis but patients with evidence of vitamin B6 deficiency may require up to 50 mg daily.
Pyridoxine can block the therapeutic effect of levodopa by enhancing its decarboxylation to dopamine, which does not enter the brain. However, it does not interfere with the combined preparations of levodopa and a decarboxylase inhibitor.
Pyridoxine tablets should be stored in well-closed containers.