Infusion Therapy involves the administration of medication through a needle or catheter. It’s prescribed when a patient’s condition is so severe that it cannot be treated effectively by oral medications.  Typically, “Infusion Therapy” means that a drug is administered intravenously, but the term also may refer to situations where drugs are provided through other non-oral routes, such as intramuscular injections and epidural routes (membranes surrounding the spinal cord).