A formulation approved both for use in the eye/ear is classified in S03. Formulations approved for eye, ear and nose are also classified in S03. Formulations only licensed for use in the eye or the ear are classified in S01 and S02, respectively.

Most of the drugs in this group are topical preparations. Systemic preparations with clear ophthalmological indications are also classified in this group.
Small amounts of antiseptics in eye preparations do not influence the classification, e.g. benzalkonium.
See also S03 - Ophthalmological and otological preparations.

This group comprises topical drugs used for diagnosing diseases in the eye. Mydriatics and cycloplegics used as diagnostic aids are classified in S01F.
Diagnostic agents for systemic use for ophthalmological diagnoses, e.g. fluorescein injection, are classified in V04CX - Other diagnostic agents.