What are the key nursing considerations for subcutaneous insulin injection?

Rotate injection sites among the abdomen, thighs, upper arms, and buttocks to prevent lipodystrophy, which is thickening or wasting of tissue from repeated injections in the same spot. The abdomen provides the fastest and most consistent absorption. Do not inject within two inches of the umbilicus. Inject at a 90-degree angle for most patients. Do not massage the injection site. Rapid-acting insulin should be given within 15 minutes before meals.