why do you take b12 injections Feeling worse after Injection: Answering concerns B12 Injection Dosage and Frequency:

Although some of the supplement doses are very high (for instance, 500 or 1,000 micrograms when a healthy adult only needs 2.4 micrograms per day), your body only absorbs what it needs and pees the rest out

Some individuals may struggle to absorb B12 through diet alone especially those with certain dietary restrictions or medical conditions

This depends on your health needs

A seminal cost analysis published in Canadian Family Physician (2001) projected that switching patients from intramuscular B12 injections to oral supplements could save between $2.9 million and $17.6 million depending on the population studied with one Ontario analysis estimating $14.5 million in savings for 110,000 elderly patients