MYDRIATICS – INTRODUCTION
A drug that causes the pupil of the eye to dilate; used to aid eye examinations
MYDRIATICS – INDICATION
Mydriatic agents are medicines that cause the pupil of the eye to dilate. Topical mydriatic agents are applied directly to the eye to assist during eye examination and to treat inflammatory eye conditions such as iritis and cyclitis.
MYDRIATICS – INFORMATION
Dilating drops can sting and burn when first inserted. This effect normally lasts only a minute or two, according to the Mayo Clinic. Eye irritation or reddening may occur. Drops that are strictly mydriatics, with no cycloplegic drug added, like phenylephrine, dilate the eye for several hours. The side effects of pupil dilation are light sensitivity and blurred vision. Headache and pain in the brow can also occur, according to the Mayo Clinic.
Large doses of anticholinergic drugs (atropine, glycopyrrolate) produced mydriasis in a group of adults with no eye abnormalities except strabismus, though the usual intramuscular and intravenous doses of these drugs do not have this tendency. Such large doses are often given intravenously during general anesthesia to prevent the side effects of neostigmine methylsulfate, which is used to reverse the effect of nondepolarizing muscle relaxants. Neostigmine methylsulfate (Prostigmin) reduced the mydriatic effect when given intravenously in conjunction with atropine or glycopyrrolate. Mydriasis was more likely to occur in lightly pigmented eyes than in eyes with dark irides. Pilocarpine eyedrops instilled at the beginning of anesthesia caused miosis that persisted after the large intravenous doses of atropine or glycopyrrolate were given. To prevent an attack of acute angle-closure glaucoma in any patient who is to receive large doses of anticholinergic drugs during general anesthesia, miotic drug therapy should be continued before, during, and after anesthesia at the same frequency as when awake.