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.
Intramuscular injections are used to deliver drugs and vaccines. They are a common practice in modern medicine. Several drugs and almost all inactivated vaccines are delivered this way.
Intramuscular injections are used when other types of delivery methods are not recommended. These include oral (swallowed into the stomach), intravenous (injected into the vein), and subcutaneous (injected just under the layer of skin).
The speed of absorption is faster for intramuscular injection compared to subcutaneous injection. This is because the muscle tissue has a greater blood supply than the area just under the skin. Muscle tissue may also hold a larger volume of medication than subcutaneous tissue.
Intramuscular injection may be used instead of intravenous injection because some drugs are irritating to veins. Sometimes, a suitable vein cannot be located. It may be used instead of oral delivery because some drugs are destroyed by the digestive system when a drug is swallowed
Intramuscular injections are often given in the following areas:
The uptake of drugs from the thigh is slower than from the arm. The thigh may be used when the other sites are not available or if a patient needs to administer the medication on their own while lying down. A ventrogluteal site such as the buttocks is the safest site for adults and children over seven months of age. It is deep and not close to any major blood vessels and nerves. The thigh is preferred for immunizations in children. The deltoid in the arm is the site most typically used for vaccines. It is rarely used for other medications because the volume of medication is too large.
All healthcare workers who administer intramuscular injections to patients should receive training and education on proper administration. Selection of the needle size and injection site depends on many factors. These include age, size of the patient, and volume of medication. An injection site should not be used if there is evidence of infection or injury at the site.
The medication is administered with a needle long enough to reach the muscle without penetrating the structures underneath.
The following general procedure may be used for intramuscular injections:
Complications of intramuscular injections include:
Many children often experience anxiety due to the use of needles and fear of pain. A nurse practitioner should use extra precautions around children to help ease the child’s worries and prevent injury.