Does an intramuscular injection invalidate the fast?

An intramuscular or other type of injection, if it is in the sense of food or drink, then it is nourishing, and it invalidates and nullifies the fast. This is usually administered intravenously. However, if it is for treatment and not for nourishment, then the more apparent ruling is that it does not invalidate the fast, because it does not violate the intent of the Lawgiver and does not fall under the definition of what breaks a person's fast.