Black pepper
Black peppercorns are mentioned in Ayurveda, Siddha and Unani medicine in India. The 5th century Syriac Book of Medicines prescribes pepper (or perhaps long pepper) for illnesses such as constipation, diarrhea, earache, gangrene, heart disease, hernia, hoarseness, indigestion, insect bites, insomnia, joint pain, liver problems, lung disease, oral abscesses, sunburn, tooth decay, and toothaches. Various sources from the 5th century onward also say pepper is good to treat eye problems. Often special ointments made with pepper have to be applied directly to the eye. There is no current medical evidence that any of these treatments has any benefit; pepper applied directly to the eye would be quite uncomfortable and possibly damaging.