Infusion therapy involves the administration of medication through a needle or catheter. It is prescribed when a condition is so severe it cannot be treated effectively by oral medications, or there are no oral therapies that meet the needs of the patient. Typically, infusion therapy means that a drug is administered intravenously, but the term also may refer to subcutaneous infusions. Prescription drug therapies commonly administered via infusion include intravenous immunoglobulin (IVIG), antibiotics, antifungals, antivirals, chemotherapy, hydration, pain management and parenteral nutrition. Infusion therapy is also provided to patients for treating a wide assortment of often chronic and sometimes rare diseases for which specialty infusion medications are effective when given on a weekly or monthly basis.