Pyridoxine (B6) Injection

Pyridoxine (B6) Injection

Available presentation(s): 5 mL. Verify the exact concentration and total active quantity on the prescription and dispensing label.

Introduction: Pyridoxine (vitamin B6) is converted to pyridoxal-5-phosphate, a coenzyme in amino-acid and neurotransmitter metabolism. Injection is reserved for situations where parenteral replacement or antidotal treatment is clinically required.

Dosage: Dose depends on deficiency, medicine-induced deficiency or specialist antidote protocols (for example isoniazid toxicity). Follow NZF/toxicology guidance. The 50 mg/mL presentation must be prescribed in milligrams with route and schedule. Avoid chronic high cumulative exposure.

Mechanisms of Action: Pyridoxal-5-phosphate supports transamination, decarboxylation, glycogen metabolism, haem synthesis and neurotransmitter production.

Contraindications & Precautions: Avoid in hypersensitivity. Repeated high doses can cause severe sensory neuropathy and ataxia. Investigate underlying deficiency and monitor neurologic symptoms during prolonged therapy.

Interactions: Reduces levodopa effect when levodopa is used without a decarboxylase inhibitor. Isoniazid, hydralazine, penicillamine and some anticonvulsants alter B6 metabolism.

Adverse Reactions / Side Effects: Injection-site reactions, nausea, headache, somnolence and hypersensitivity may occur. Chronic/excessive dosing can cause sensory neuropathy, photosensitivity and loss of coordination.

Pregnancy & Breastfeeding: Appropriate nutritional replacement is acceptable when indicated; high-dose or antidotal use requires obstetric/toxicology oversight. Pyridoxine enters breast milk.

Storage: Store under the conditions stated on the Optimus dispensing label and product-specific worksheet. Protect from light where labelled. Do not freeze unless explicitly validated. Maintain cold chain if the label requires refrigeration. Do not use after the assigned beyond-use date or if there is visible particulate matter, precipitation, colour change, loss of container integrity or evidence of improper storage. Once entered, follow the validated in-use time; do not assume a compounded vial is multi-dose.

References

• New Zealand Formulary (NZF), current online edition; product-specific approved data sheets where available; USP Pharmaceutical Compounding—Sterile Preparations; and Optimus Healthcare validated formulation, sterility/endotoxin controls and assigned beyond-use date.
• DailyMed. Thiamine Hydrochloride, Pyridoxine Hydrochloride, Hydroxocobalamin and Levocarnitine injection labels, current editions. https://dailymed.nlm.nih.gov/
• NIH Office of Dietary Supplements. Health Professional Fact Sheets (vitamins and minerals), current online editions. https://ods.od.nih.gov/factsheets/list-VitaminsMinerals/