Comparison of the angles of insertion for intramuscular (IM), subcutaneous, and intradermal injections. An IM injection is given at a 72- to 90-degree angle. A subcutaneous injection is usually given at a 45-degree angle, but may be given at up to a 90-degree angle, if a short needle is used or if the person is heavy. The intradermal injection is given holding the syringe nearly parallel to the skin (10- to 15-degree angle).