Comparative Efficacy of Intranasal, Intramuscular, and Intravenous Vitamin B12 Therapy for Hematological Recovery in Vitamin B12 Deficiency Anemia: A Randomized Controlled Trial.
Am J HematolJul 2, 2026 (epub)
Santosh Kumar Singh, Rahil Arora, Suman Kumar Pramanik et al.
✦ AI-curated · Sources linked
In 30 seconds
This randomized controlled trial compared the efficacy of intranasal, intramuscular, and intravenous vitamin B12 therapy in 153 adults with vitamin B12 deficiency anemia. All routes resulted in significant hematological recovery, with mean hemoglobin increases of +2.48, +1.80, and +2.18 g/dL, respectively. However, adjusted analyses showed no significant intergroup differences in hemoglobin recovery.
Key findings
- Mean hemoglobin increase was +2.48 g/dL for intranasal, +1.80 g/dL for intravenous, and +2.18 g/dL for intramuscular therapy.
- LDH normalization was greater with parenteral routes, with a significant difference (H=8.17, p=0.017).
- Intramuscular therapy resulted in the most pronounced reticulocytosis (H=13.93, p=0.001).
- Baseline hemoglobin, vegan diet, and age were independent predictors of treatment response.
Why it matters
Understanding the comparative efficacy of different vitamin B12 administration routes can guide clinicians in selecting appropriate treatment options for patients with vitamin B12 deficiency anemia, especially in resource-limited settings.