Injection is a type of dosage form that involves administering medication directly into the body through a needle. This method of delivery allows for quick and effective delivery of medication, as it bypasses the digestive system and enters the bloodstream directly. Injections can be given intravenously (into a vein), intramuscularly (into a muscle), subcutaneously (under the skin), and intradermally (into the skin). Injections are commonly used for medications that cannot be taken orally or need to be delivered quickly, such as antibiotics, pain relief medication, and vaccines. It is important to follow proper techniques when administering injections to avoid complications such as infections and tissue damage.