Enhanced Urinary Excretion of Co⁶⁰ Vitamin B₁₂ Produced by Delayed Release Capsules

1. Patients without known hematologic disease were given 8 µg. (0.2 µc. Co⁶⁰ vitamin B₁₂ as a water solution or in various types of delayed release capsules.

2. All groups showed approximately equal fecal excretion. However, the cobalt⁶⁰-labeled vitamin B₁₂ delayed release capsules showed a greater urinary excretion after a loading dose of stable B₁₂ than did the water solution of labeled vitamin B₁₂.