This Randomized, Clinical Trial Evaluates the Efficacy of Oral Versus Sublingual Vitamin B12 Supplementation in Correcting Early-onset Vitamin B12 Deficiency in Adult Patients Using Proton Pump Inhibitors (PPIs). The Primary Outcome is the Change in Serum Vitamin B12 Levels Over a 6-week

Sublingual Versus Oral Vitamin B12 for Acute Hypovitaminosis B12 Secondary to Proton Pump Inhibitors: A Prospective Randomized Study

This randomized, clinical trial evaluates the efficacy of oral versus sublingual vitamin B12 supplementation in correcting early-onset vitamin B12 deficiency in adult patients using proton pump inhibitors (PPIs). The primary outcome is the change in serum vitamin B12 levels over a 6-week treatment period. Secondary outcomes include changes in homocysteine levels, hemoglobin levels, and patient-reported satisfaction.

Inclusion Criteria:

• Age 18-70.
• PPI use for 1-6 months (new users).
• Serum B12 between 150-300 pg/mL.
• No known prior B12 supplementation.

Exclusion Criteria:

• History of long-term GI disease (e.g., Crohn's, celiac).
• Previous gastrectomy/bariatric surgery.
• Baseline anemia with hemoglobin <9 g/dL.
• Severe renal or liver failure.