Final answer:
The 3 methods of drug administration include oral, enteral, and parenteral. Oral administration is generally preferred for home administration, but when that's not possible, parenteral administration is used.
Step-by-step explanation:
The 3 methods of drug administration include oral, enteral, and parenteral. The route of administration is an important consideration for drug therapy. Administration of drugs orally is generally preferred because it is convenient for home administration. Some drugs that are not absorbed easily from the gastrointestinal tract are available as topical preparations for skin infections. When a drug is not absorbed in the GI tract or when a patient can't take oral medications, administration by a parenteral route (intravenous or intramuscular injection) is preferred and typically performed in healthcare settings.