The research was performed at the Faculty of Veterinary Medicine of the Latvia University of Agriculture. At the moment the research in veterinary anaesthesia is in its infancy stage. The aim of this study was to determine the effects of the acepromazine maleate on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in a dog's eye. Ten adult dogs of different age, breed and sex were examined clinically and ophthalmologically. All animals were clinically and ophthalmologically healthy. Animals received acepromazine intramuscularly. IOP and HPD were measured every 5 minutes for the total period of 60 minutes. It was established that the acepromazine maleate intramuscular injection causes an IOP decrease in booth eyes. A significant IOP decrease was observed from 35 till 60 minutes after the acepromazine injection. The pupil contraction was observed 5 minutes after the treatment and continued to contract till the end of the research. As acepromazine maleate causes a significant decrease of intraocular pressure, it is not contraindicated to be used in the case of corneal trauma, perforation, glaucoma and corneal ulcers.

The objective of this study was to determine the effects of topical 1% atropine sulphate and systemic atropine sulphate on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in dog’s eyes. Ten adult dogs for each treatment were used in this study. Dogs of different age, breed and sex were examined clinically and ophthalmologicaly. All animals were clinically and ophthalmologically healthy. One drop of topical 1% atropine sulphate was used in ten dogs unilaterally, with the contralateral eye acting as a control. IOP and HPD were measured every 5 minutes. In ten dogs systemic atropine sulphate were used intramuscularly (IM) with IOP and HPD measured every 5 minutes. In both study phases IOP and HPD were measured over a total duration of 60 minutes. After unilateral application of topical atropine, IOP increased significantly in the treated eye. A maximum average IOP of 20.3 mmHg in the treated eye was observed 20 minutes after treatment. Maximal pupil dilatation in the treated eye was observed 35 min after treatment. Measurements made after systemic atropine showed an IOP increase in both eyes, showing maximum average IOP increase 25 minutes post-treatment. Maximum average values of HPD were obtained 25 minutes after treatment. The HPD started to decrease 30 minutes after treatment but it was still significantly higher than before treatment (P is less than 0.05). Because of atropine sulphate’s ability to cause significant increase in IOP, it should not be used for diagnosis and treatment of glaucomatous eyes.