AMA Manual of Style - Stacy L. Christiansen, Cheryl Iverson 2020

Administration of Drugs
Correct and Preferred Usage

When describing the administration of drugs, buccal, cutaneous, dermal, inhalational, intra-articular, intracardiac, intramuscular, intrathecal, intravenous, intraventricular, intravitreal, nasal, ocular, oral, otic, parenteral, rectal, subconjunctival, subcutaneous, sublingual, topical, transdermal, and vaginal are acceptable terms when these are the usual or intended routes of administration. Except for systemic chemotherapy, however, drugs are usually neither systemic nor local but are given for systemic or local effect.

Some topical corticosteroid ointments produce systemic effects.

Oral penicillin is often preferred to parenteral penicillin.

Intravenously injected heroin may be contaminated.

Exceptions: Local anesthetics are a class of drug. Techniques for delivering anesthesia are general, local, and regional.