Mydriaticum - Tropicamide

Tropicamid (Mydriaticum) used to induce mydriasis (one drop per eye). 

A solution containing tropicamide 1% and benzalkonium chloride 0.01% (Mydriaticum) was introduced in 1979 to obtain mydriasis and cycloplegia for diagnostic purposes. Contact dermatitis from ophthalmic formulations is common, preservatives being the most frequent causes (3). Allergic contact dermatitis has been reported, implicating tropicamide as a sensitizer (4). 

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. 

Monkeys were tranquilized with ketamine hydrochloride (Imalgene 1000, Rhone Merieux, Lyon, France), 10 mg/kg of body weight, IM. Pupils were dilated with tropicamide (Mydriaticum, MSD-Chibret, Paris, France) and phenylephrine (Neosynephrine 10% Chibret, MSD-Chibret, Paris, France), 20 minutes before recording. The electrodes were put into position after a minimum of 15 minutes of dark adaptation. The animals were then placed in a dark room. 

As part of the routine evaluations conducted in preclinical safety studies, ophthalmic examinations were performed on study weeks 7,12,16 and 18 with an indirect ophthalmoscope after 0.5% tropicamide (Mydriaticum Chibret) instillation. 

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