Mydriatic agent

Goskonda VR, Khan MA, Hutak CM, Reddy IK. Permeability characteristics of novel mydriatic agents using an in vitro cell culture model that utilizes SIRC rabbit comeal cells. J Pharm Sci 88 180-184 (1999). 

It is a vasopressor agent with some structural similarity to adrenaline and has a powerful alpha receptor stimulant action. The pressor response is accompanied by reflex bradycardia. It is used as a nasal decongestant and mydriatic agent and also in the treatment of paroxysmal supraventricular tachycardia. 

It is used for refraction testing in adults and as mydriating agent for fundoscopy. It has quickest and briefest action. 

Phenylephrine is an effective mydriatic agent frequently used to facilitate examination of the retina. It is also a useful decongestant for minor allergic hyperemia and itching of the conjunctival membranes. Sympathomimetics administered as ophthalmic drops are also useful in localizing the lesion in Horner s syndrome. (See An Application of Basic Pharmacology to a Clinical Problem.)... 

The doctor made a diagnosis of an acute attack of closed-angle glaucoma, as a result of his narrow drainage angles and the probable exposure to a mydriatic agent. 

Failure to use drugs when clinically indicated, particularly mydriatic agents for diagnosis, is a significant source of liability claims. A hypothetical example illustrates how the standard of care can be applied if drugs are not used appropriately for diagnostic purposes. If a patient has received a blow to the eye from a fist, ball, or other blunt object, the optometrist must rule out the possibility of a retinal break. To perform a reasonable examination, one that conforms to the expected standard of care, dilation of the pupil is necessary. In feet, it may be argued that examination of the retinal periphery with a binocular indirect ophthalmoscope is required under these circumstances. Therefore feilure to dilate the pupil and view the retinal periphery fells below the standard of care. If for some reason the optometrist cannot perform a dilated examination, the patient must be referred to another clinician so that the appropriate evaluation can be performed. 

Topical instillation of a 1% solution in eyes with normal adrenergic innervation causes mydriasis and also some vasoconstriction. However, hydroxyamphetamine is used only as a mydriatic agent. After topical application onset occurs within 15 minutes, maximum dilation occurs within 60 minutes, and the duration of mydriasis is approximately 6 hours. The U.S. Food and Drug Administration has labeled this drug as a Pregnancy Category C. 

Because tropicamide is reported to be devoid of vasopressor effects in adults, it is one of the safest mydriatic agents for use in patients with systemic hypertension, angina, or other cardiovascular disease. Tropicamide has also been shown to be the safest agent (as indexed by changes in blood pressure and heart rate) for dilated retinal examinations in neonates. Additional information on pupil dilation in infants may be foimd in Chapter 8. 

Priestly BS, Medine MM, Phillips CC. Cydomydril a new mydriatic agent.AmJ Ophthalmol 1960 49 1033-1034. 

Suprefact buserelin. suprofen [ban, inn, jan, usan] (R 25061 Profenal ) is a member of the propionic acid series, and is a CYCLOOXYGENASE INHIBITOR With NSAID ANALGESIC. ANTIINFLAMMATORY and ANTIPYRETIC activity. It was formerly used systemically, but now is used topically to the eye as a mydriatic agent (to inhibit Intraoperative miosis). Surgam tiaprofenic acid. 

Mydriatic agents containing tropicamide and phenylephrine hydrochloride (nurses)... 

Okamoto H, Kawai S (1991) Allergic contact sensitivity to mydriatic agents on a nurse s fingers. Cutis 47 357-358 Ophaswongse S, Maibach HI (1994) Alcohol dermatitis allergic contact dermatitis and contact urticaria syndrome a review. Contact Dermatitis 30 1-6... 

The ERG S were recorded after a period of dark adaptation lasting 30 minutes. At the beginning of this period and again 15 minutes later a mydriatic agent (tropicamide Mydriaticum) was instilled into the eyes. We decided to adopt a 30 minutes dark adaptation period in order to have less variation in wave amplitudes. However, due to the Mnd of stimulator which was used, the less variable and therefore most interpretable values were latencies and not amplitudes. Consequently, it was decided to measure latencies only. 

K. Yoshikawa and S. Kawahara, Contact allergy to atropine and other mydriatic agents. Contact Dermatitis, 1985, 12, 56-57. 

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