Intramuscular injections are given into specific muscles with the most common injection sites being the deltoid, vastus lateralis, and gluteal muscles.
Intramuscular injections are given into specific muscles with the most common injection sites being:
- The deltoid muscle of the upper arm
- (typically used for vaccines and cannot be used for self-injecting)
- The gluteal muscle of the buttock
- (injecting antibiotics, vitamins)
- (commonly done in the ventrogluteal site)
- The vastus lateralis muscle of the thigh
- (most commonly in infants for vaccination)
- (used for self-injections in adults and when other sites cannot be used)
How do you give an intramuscular injection?
Typically a healthcare professional will provide training and education before asking patients to administer intramuscular injections to themselves or another person.
Here are the steps to safely administer an intramuscular injection:
- Wash your hands
- Thoroughly wash your hands with soap and warm water, paying close attention to the spaces between your fingers and under your fingernails.
- Gather your necessary supplies
- This includes having the following at the ready:
- Alcohol wipes
- Sterile gauze pad
- Cotton ball
- Bandage
- Puncture-resistant container to dispose of the needle
- New needle and syringe
- The medication
- This includes having the following at the ready:
- Prepare the injection site
- Locate the injection site and gently spread the skin between two fingers, keeping the muscles relaxed.
- Clean the area with an alcohol wipe and allow it to air-dry.
- Prepare the syringe and vial
- Clean the rubber stopper with an alcohol wipe.
- Remove the syringe cap and draw air in by pulling back the plunger.
- Fill the syringe with air up to the same level as the medication dose.
- Remove the cap of the needle and push it through the top of the vial.
- Inject the air into the vial, and then turn the vial and syringe upside down.
- Drawback the plunger to fill the correct medication dose.
- Remove any air bubbles by gently tapping the syringe and pressing the plunger.
- Inject the medication
- Insert the needle into the proper muscle at a 90 degree angle.
- Stabilize the syringe with the index finger and thumb.
- Use your other hand to pull back on the plunger to look for blood.
- If there is blood, it means you're in a blood vessel and not the muscle.
- Withdraw and start over with a new needle and injection site.
- If there is no blood, press down on the plunger to inject the medication.
- Remove the needle
- Remove the needle quickly and dispose of it in the puncture-resistant container.
- Press and bandage the injection site
- Use the gauze pad to apply light pressure to the injection site.
- Apply a bandage to the site if necessary.
When is an intramuscular injection used?
Intramuscular injection is the method of administering medications deeply into the bulk of specific muscles. It is commonly used for administering medications and vaccines, which helps the medication quickly absorb into the bloodstream.
These injections are used when other modes of administration cannot be used, such as:
- Oral (ingestion)
- Subcutaneous tissue (injected into the fatty tissue just beneath the skin)
- Intravenous (injected into the vein)
Intramuscular injections can be used for depot injections that provide a slow, continuous release of medicine over a prolonged period. Additionally, these injections require less effort and time for administration, making them less painful than intravenous injections.
Which medications are given as intramuscular injections?
There are many medications that are given as intramuscular injections. Some drugs are given this way because they are irritating to the veins and cannot be given intravenously.
The most common drugs given as intramuscular injections include:
- Antibiotics
- Immunoglobulin
- Hormones such as testosterone and medroxyprogesterone
- Epinephrine (as an auto-injector in severe allergic reactions)
When is an intramuscular injection avoided?
Doctors may avoid intramuscular injections depending on the drug. If the drug that is given intramuscularly is not good for you, an intramuscular injection will be avoided.
Intramuscular injections are generally avoided in people with:
- Low platelet count
- Clotting problems
- Hypovolemic shock
- Myopathy
- Muscle atrophy
If your healthcare provider thinks that an intramuscular injection may cause potential damage to the blood vessels during the injection, they will avoid it.
Moreover, intramuscular injections will be avoided if the injection site has:
- Infection
- Swelling
- Irritation or redness
- Birthmarks or moles
- Areas with scar tissue
What are the complications of intramuscular injections?
Experiencing some discomfort and mild, short-lived pain after intramuscular injection is normal.
Some people may experience symptoms, such as injection site pain, and discomfort that lasts for a few days and disappears on their own.
Possible complications of intramuscular injections at the injection site include:
- Severe pain
- Bruising where injected
- Tingling or numbness
- Redness, swelling, or warmth
- Uncontrolled bleeding
- An abscess (pus-filled pockets)
- Gangrene (tissue death)
- Risk of infections (if an unsterilized needle is used)
Depending on the drug, allergic reactions in the form of facial swelling, itching, and breathing difficulties may occur.
It is normal to feel anxious before getting intramuscular injections. If you have any concerns about the technique or medication or vaccine being administered, get them cleared from your pharmacist or healthcare provider.