PYRIDOXINE HYDROCHLORIDE- pyridoxine hydrochloride injection, solution
APP Pharmaceuticals, LLC
100 mg/mL
DESCRIPTION
Pyridoxine Hydrochloride Injection, USP is a sterile solution of pyridoxine hydrochloride in Water for Injection. Each mL contains 100 mg pyridoxine hydrochloride and 0.5% chlorobutanol anhydrous (chloral deriv.). pH adjusted with sodium hydroxide if necessary (2.0 � 3.8).
Pyridoxine hydrochloride is a colorless or white crystal or a white crystalline powder. One gram dissolves in 5 mL of water. It is stable in air and is slowly affected by sunlight.
CLINICAL PHARMACOLOGY
Natural substances that have vitamin B6 activity are pyridoxine in plants and pyridoxal or pyridoxamine in animals. All 3 are converted to pyridoxal phosphate by the enzyme pyridoxal kinase. The physiologically active forms of vitamin B6 are pyridoxal phosphate (codecarboxylase) and pyridoxamine phosphate. Riboflavin is required for the conversion of pyridoxine phosphate to pyridoxal phosphate.
Vitamin B6 acts as a coenzyme in the metabolism of protein, carbohydrate, and fat. In protein metabolism, it participates in the decarboxylation of amino acids, conversion of tryptophan to niacin or to serotonin (5-hydroxtryptamine), deamination, and transamination and transulfuration of amino acids. In carbohydrate metabolism, it is responsible for the breakdown of glycogen to glucose-1-phosphate.
The total adult body pool consists of 16 to 25 mg of pyridoxine. Its half-life appears to be 15 to 20 days. Vitamin B6 is degraded to 4-pyridoxic acid in the liver. This metabolite is excreted in the urine.
The need for pyridoxine increases with the amount of protein in the diet. The tryptophan load test appears to uncover early vitamin B6 deficiency by detecting xanthinurea. The average adult minimum daily requirement is about 1.25 mg. The ��Recommended Dietary Allowance�� of the National Academy of Sciences is estimated to be as much as 2.2 mg for adults and 2.5 mg for pregnant and lactating women. The requirements are more in persons having certain genetic defects or those being treated with isonicotinic acid hydrazide (INHJ) or oral contraceptives.
INDICATIONS AND USAGE
Pyridoxine Hydrochloride Injection is effective for the treatment of pyridoxine deficiency as seen in the following:
Inadequate dietary intake.
Drug-induced deficiency, as from isoniazid (INH) or oral contraceptives.
Inborn errors of metabolism, e.g., vitamin B6 dependent convulsions or vitamin B6 responsive anemia.
The parenteral route is indicated when oral administration is not feasible as in anorexia, nausea and vomiting, and preoperative and postoperative conditions. It is also indicated when gastrointestinal absorption is impaired.
The chemical name is 2-methyl-3-hydroxy-4,5-bis (hydroxymethyl) pyridine hydrochloride.
