What is the purpose of intradermal injections?

Intradermal injections are primarily used for testing purposes, notably for allergies and tuberculosis exposure. This method involves the administration of a small amount of substance into the dermis, the layer of skin just below the epidermis, allowing for a localized reaction to take place. The primary reason for using this route in tests such as the Mantoux test for tuberculosis is that it produces a controlled immune response, which can be easily monitored for signs of reaction.

Vaccines typically require different administration routes, such as intramuscular or subcutaneous, to ensure proper immune response and absorption of the vaccine components. High doses of medications are generally avoided in intradermal injections due to the limited volume that can be administered effectively without causing irritation or an adverse reaction. Similarly, intradermal injections are not suitable for short-term pain relief; other routes of administration, such as subcutaneous or intravenous, are preferred for that purpose to ensure appropriate pain management and medication delivery.