Does eyedrop invalidate fasting?
According to the information obtained from experts of the field, medication dropped in the eyes is in very low amount (50 microliters which is equal to 1/20 of 1ml); some of it flows out through blinking, and some of it is absorbed by pores on channels connecting eye and nose and mucosa, and enters into body. Moreover, this process does not mean eating and drinking. Therefore, eyedrop does not invalidate fasting (Decision by HBRA dated 22.09.2005; see. Kasani, Bada’i, II, 98).
Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS