Hydroxocobalamin (Vitamin B12)

• B12 deficiency in pregnancy
• Pernicious anaemia
• Post-bariatric surgery pregnancy

Provides cobalamin cofactor for methionine synthase and methylmalonyl-CoA mutase — restores DNA synthesis and myelin.

• Neurological signs → load daily × 2 weeks
• Check MMA + homocysteine if uncertain
• Give folate only AFTER B12 replaced

Loading (no neuro)

1 mg IM × 3/week for 2 weeks

Neurological

1 mg IM alternate days until improvement, then 1 mg every 2 months

Maintenance

1 mg IM every 3 months

• AbsoluteHypersensitivity to cobalt or cobalamins

• Injection-site pain
• Red urine (harmless)
• Rare hypersensitivity

• • Safe throughout pregnancy and lactation
• • Prevents neonatal B12 deficiency in vegan/bariatric mothers

• Metformin

  Caution

  Long-term ↓ B12 absorption

• 💡 Give BEFORE folate in mixed deficiency to avoid precipitating subacute combined degeneration
• 💡 Vegan mothers: check B12 preconception and each trimester