Why are intramuscular injections preferred?

Answer 1

Intramuscular injections are preffered for delivery of many medications as it is the fastest and simplest way to infect drugs. Adrenaline (epinephrine to the yanks) is the classic example given during anaphalctic shock. Here a fast delivery of the drug is key and so waiting for a trained expert to be found would take too long. Intramuscular inveftion can be given by anyone simply by finding a large muscle (often the gluteus maximus) and injecting it, that simple. The next most simple is subcutaneous. This is again fairy simple but requires being shown how to perform and is a common mode of insulin injection in diabetics. Finally intravenous is the third form of injection but this requires finding a vein which takes some degree of skill and training.

Answer 2

Intramuscular injection is easier for delivering the drug as there is a bigger area to target whereas for intravenous injection, the drug has to be injected into the vein. Drugs injected intramuscular also have longer duration and slower onset of action as it takes longer for the drugs to spread around.