How Do I Administer an Intradermal Injection?

​When drugs are administered to patients, it can be accomplished in several different ways. A drug can be given by mouth or injected into a vein. Injections are also performed into different sites, including the muscle, the fatty layer of the skin, and the dermis, which is referred to as the intradermal injection. To administer an intradermal injection, choose a 25-gauge needle that is about 1 to 2 centimeters (0.4 to 0.8 inches) long and penetrate the site of injection at a 15-degree angle from the skin. The forearm and upper arm are typical intradermal injection sites.​​

Before you actually give this injection, as with any type of drug administration, you need to be certain that you are qualified to give drugs to patients and that you follow what are known as "The Five Rights of Drug Administration" to which all healthcare professionals adhere.​ These include administering the right medication in the right dosage in the right route at the right time to the right patient. Following the Five Rights significantly diminishes the chances of making an error.

Before administering the injection, be sure to wash your hands to sterilize them. Do not touch the patient, medicine vial, or syringe before this is done. It is necessary for infection control protocol. Then, put on your gloves and be certain they are latex-free.

Check the patient's name and explain what you are about to do. Most importantly, tell him or her what to expect from receiving an intradermal injection such as a small blister-like bump just underneath the skin. If it is a tuberculin test, be sure to tell him or her when he or she is supposed to come back and have the results read, which is typically three days from the date of injection.

The dermis, where the injection will be given, is the layer of the skin that is located just beneath the epidermis, the superficial layer of the skin. The subcutaneous layer of the skin is deeper, underneath the dermis. This is where you want to avoid depositing the shot as it will affect how the drug is absorbed in the body. Any deeper than this, and you will be in the muscle.

In order to perform the intradermal injection, the syringe must be inserted at an angle of about 15 degrees, which nearly places the syringe flat against the patient's skin. Placing the syringe at this angle ensures that you will inject the medication into the dermal layer. Slowly inject the medicine until a bubble appears just underneath the skin and then withdraw the needle. Finally, you should clean the site once again with an alcohol pad.