Subcutaneous and Intramuscular injections?

Question

Why are some injections given subcutaneously and some into the muscle? What's the difference between these two types of shots?

Thanks!

Answer 1

Subcutaneous (SQ) injections are given under the skin, where intramuscular (IM) injections are given in a large muscle mass, like the deltoids or gluteals.  Drugs given IM are often more irritating or likely to cause local necrosis than drugs given SQ.  Morphine, for example, can be given SQ, where if chlorpromazine is given SQ, it causes sores and scarring of the skin at the injection site.

DK

Answer 2

In general, medications are administered subcutaneously when a slower, more prolonged effect is desired (e.g., insulin, many immunizations, heparin -- an anticoagulant). IM injections are best for larger volumes of medication and when faster absorption of the medicine is desired (e.g., antibiotic).

Subcutaneous injections are administered with shorter and smaller needles than an IM; volume of medication less than 1 cc.

Answer 3

this is usually based on the pharmacology recommendation for administration.

muscular and subcutaneous injections have different absorption

factors.