Gluteal-area intramuscular injection

Fig. 6 A technique for gluteal-area intramuscular injection. (From Refl l)...

The absorption rate after intramuscular administration differs depending on type of muscle chosen. Studies have shown that intramuscular injections result in different plasma concentrations of narcotics and perceived pain relief depending oti the type of muscle used for administration. This was also found for the response to vaccination and use of antibiotics and insulin [7]. Absorption of active substances from the intramuscular site depends mi the quantity and composition of the connective tissue and the rate of vascular perfusion of the area. Blood flow in the muscles varies (it is increased in deltoid muscle) and is influenced by the exercise of the muscle and morbidity. The muscles are covered with the subcutaneous connective tissue, a hpid layer (adipose layer) and the skin. The thickness and the Upid content of these tissues are different in different body areas. The subcutaneous fat layer at the gluteal intramuscular injection site is thicker in females (mostly > 3 cm) than in males. The medication should be administered with a needle long enough to reach the muscle without penetrating underlying structures. 

The rate at which dmg particles are absorbed is determined by the amount of blood vessels there are in the area where the dmg is administered. Dmg particles are nearly instantaneously absorbed if the dmg is injected intravenously (IV). A slower absorption rate occurs if the dmg is administered intramuscularly (IM). The IM rate is dependent on the amount of blood vessels there are at the site of the injection. For example, a dmg is absorbed faster in the deltoid (arm) muscle than in the gluteal (butt) muscle because there are more blood vessels in the deltoid muscle. Dmgs injected in subcutaneous (SC) tissue are absorbed slower than those injected via IM injections because there are fewer blood vessels in subcutaneous tissues than in muscles. 

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