Semaglutide has an extensive base of large-scale RCTs
Method Absorption Rate Advantages Disadvantages Oral pills 1.2-40% depending on intrinsic factor Convenient, widely available Poor absorption, especially with age or GI issues Sublingual Slightly better than pills No need for intrinsic factor, easy to use Still less effective than injectable forms In-clinic IM injection Nearly 100% Highly effective, professionally administered Requires clinic visits, potential travel and waiting time At home B12 injection Nearly 100% Highly effective, convenient, no travel needed Requires training, prescription, and comfort with self-injection IV infusion 100% Immediate delivery to bloodstream Most expensive, requires professional administration For many people especially those with serious deficiencies, digestive disorders, or pernicious anemia at home B12 injection offers the sweet spot of effectiveness and convenience
Vitamin B12 in neurology and ageing
Do not use the vial beyond its labeled expiration date
But their consistency is what separates short-term weight loss from lasting change
