While surgeons, gynecologists, and even authorities on internal medicine have on frequent occasions looked with little faith on the efficiency of drug medication, an attitude of drug nihilism cannot be imputed to the ophthalmologist. Indeed, some of the most important pharmacologic contributions have been in the field of ophthalmology, and some of the most strikingly beneficial therapeutic effects have been produced in the treatment of eye conditions. We need but mention the employment of atropin, cocain, physostigmin, epinephrin and many other mydriatics, miotics, astringents, analgesics and antiseptics.
When we consider the highly developed blood and lymph supply of the eye and its appendages, especially the patent tear ducts, it is surprising that so few cases of drug absorption and intoxication through them are on record. So few are the cases found in the literature that many physicians deny the possibility of such absorption through the conjunctiva and the lacrimal apparatus,
MACHT DI. THE ABSORPTION OF APOMORPHIN AND MORPHIN THROUGH THE CONJUNCTIVA. JAMA. 1917;LXVIII(17):1230. doi:10.1001/jama.1917.04270040218003