vitamin b12 injection guidelines 1000 mcg/mL Optimal Vitamin B12 Dosage and

Features that distinguish acneiform eruptions from acne vulgaris are: a positive time relationship between the introduction of the drug and the onset, a sudden and uncommon age of onset, pruritus, a monomorphic pattern and an involvement of seborrheic and extra-seborrheic areas such as the face, the neck, shoulders, arms, chest, and back [1,8]

This suggests to me that the absorption under the tongue is not as good as most people think

PeakForm states that each production lot undergoes independent analytical testing before release, with results documented in a lot-specific Certificate of Analysis

No two people are alike, meaning the injection is going to have different effects on every individual