This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
We have already noted characteristic arsenical effects upon the membrane of the mouth and intestinal canal. The lips, the nose, especially at its orifice, the anus, and the vulva often become similarly irritated and inflamed, and urethritis has been traced to medicinal doses of arsenic (Medical Record, 1878). On the mucous membrane of the eye the effect of the drug is often very early seen, so that it becomes a useful index of the degree of physiological action. Itching about the lids is first complained of, and a rough sensation as of dust in the eye; the conjunctiva is seen to be congested, and purulent secretion may be formed. Conjunctivitis is a frequent symptom in arsenical poisoning, and Dr. Taylor describes "tumid, everted lids and painful vision" in patients affected by arsenical papers, etc. (Ophthalmic Hospital Report, 1859, and British Medical Journal, ii., 1871).