What are intradermal injections (ID injections)?

From the Guidelines

Intradermal injections should only be administered with the Imovax Rabies I.D. vaccine (human diploid cell vaccine {HDCV}) for preexposure vaccination, as it is the only vaccine approved by the Food and Drug Administration (FDA) for this route and has been evaluated for safety and efficacy 1. When administering intradermal injections, it is essential to follow proper technique to ensure effective delivery of the vaccine. The injection should be given directly into the dermis layer of the skin, typically at a 10-15 degree angle with the needle almost parallel to the skin surface.

• The most common site for these injections is the inner forearm, though they can also be given in the upper chest, upper back, or scapular areas.
• A small volume (0.1-0.2 mL) is typically injected using a short, fine-gauge needle (25-27G).
• When properly administered, a small wheal or blister-like elevation appears at the injection site. The intradermal route is effective because the dermis has fewer blood vessels than deeper tissues, allowing for localized reactions and gradual absorption of substances.
• Common medications given intradermally include tuberculin skin tests (PPD), allergy testing solutions, local anesthetics, and some vaccines like BCG.
• When performing an intradermal injection, cleanse the site with alcohol and allow it to dry completely, stretch the skin taut, insert the needle bevel-up at the shallow angle, and inject slowly 1. It is crucial to note that other vaccines, such as Rabies Vaccine Adsorbed (RVA) and Purified Chick Embryo Cell Vaccine (PCEC), should not be used intradermally, as they have not been evaluated or approved for this route 1.

From the Research

Intradermal Injections

• Intradermal injections are a type of injection where the substance is injected into the dermal layer of the skin, just beneath the epidermis 2.
• Best infection control practices for intradermal injections include the use of sterile injection equipment, prevention of contamination of injection equipment and medication, and prevention of needle-stick injuries to the provider 2.
• The use of intradermal injections is medically indicated in certain situations, such as the administration of tuberculin purified protein derivative (PPD) for tuberculosis screening 3.
• Errors involving the mix-up of PPD and vaccines have been reported, highlighting the importance of proper storage, handling, and administration of vaccine and PPD products 3.

Safety Precautions

• Eliminating unnecessary injections is the highest priority in preventing injection-associated infections 2.
• The availability of best infection control practices for intradermal injections provides a reference for global efforts to achieve the goal of safe and appropriate use of injections 2.
• Institutions should commit to performance-based standards in parallel with context-specific risk assessment methods to maintain occupational health and safety programs and practices appropriate to their needs 4.

Applications

• Intradermal injections are used in various medical applications, including tuberculosis screening 3 and rabies vaccination 5.
• The rabies vaccine can prevent 99% of deaths if administered promptly after exposure 5.
• There are two main vaccination strategies for rabies prevention: pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) 5.