Final answer:
Tetracaine and proparacaine are the two common topical ophthalmic anesthetics used to numb the eye surface for medical procedures.
Step-by-step explanation:
Topical Ophthalmic Anesthetics:
Two common topical ophthalmic anesthetics are tetracaine and proparacaine. These anesthetic agents are specially formulated for use in the eye to numb the surface and facilitate procedures that may cause discomfort or pain. Unlike injectable anesthetics such as lidocaine, these are applied topically in the form of eye drops. Tetracaine and proparacaine work by blocking the nerve impulses in the eye, resulting in short-term loss of sensation in the cornea and conjunctiva.
Their onset of action is rapid, providing numbing effects typically within 30 seconds to one minute. The duration of their effects can last between 10 to 20 minutes, making them ideal for short procedures within the ophthalmologic setting. Care must be taken to use the correct dosage to avoid potential side effects such as eye irritation and prolonged numbness.