An intramuscular injection is a technique used to deliver a medication deep into the muscles. This allows the medication to be absorbed into the bloodstream quickly.
You may have received an intramuscular injection at a doctor’s office the last time you got a vaccine, like the flu shot.
In some cases, a person may also self-administer an intramuscular injection. For example, certain drugs that treat
multiple sclerosis or
rheumatoid arthritis may require self-injection.