Intravenous Vs. Intramuscular Injections

Intravenous and intramuscular injections are ways of delivering medicine. Intravenous injections are given via a syringe directly in a person's vein and into the bloodstream. Intramuscular injections are given directly into a muscle.

Dosage

The dosage for intravenous and intramuscular injections usually are similar, and generally lower than doses of comparable oral medications.

Delay in effect

Intravenous and intramuscular injections act quickly because the drug gets into the bloodstream faster than an oral medication.

Where to inject

Many intramuscular injections are given in the deltoid muscle, such as for vaccines, or in the buttocks. Intravenous injections are administered in an already established IV line or into a vein in the arm.

Injection pain

Both kinds of injections can result in pain and allergic reactions. These problems often are treated with Benadryl or an antihistamine.

Depot Medications

Depot medications are drugs given by intramuscular injection that are released slowly into the bloodstream. An example is Provera for birth control.

References

• Intravenous injection information
• Le, Tao. First Aid for Step 1. Mcgraw Medical: New York, 2009.
• Research article on glucagon injections