Can normal saline be used for practice injections?

Hypothetically, yes it can. HOWEVER, using sterile water for practicing IM injections will HURT. The sterile water is not isotonic with the cells in your body and will result in both pain and small uncontrolled muscle spasms that will subside in a few minutes. Please if possible use an isotonic sterile saline solution as this should not produce any pain or side effects.