A comparative study on efficacy of different dilutions of phenylephrine and tropicamide combination eye drops on pupil dilatation

Background: In ophthalmology (OPD), cycloplegics or mydriatics were needed for doing correct refraction and evaluation of fundus on a daily basis. Aims and Objectives: The objectives of this study were to compare the clinical efficacy and systemic side effects of different dilutions of phenylephrine and tropicamide combinations drops on pupil dilatation and to measure and compare pulse rate and blood pressure before and after giving the drug. Materials and Methods: The present study is a hospital-based interventional study conducted among patients attending to OPD of Regional Eye hospital, Visakhapatnam during April 2012–August 2012. Eighty-one patients randomly allocated to two groups (41 patients in Group 1 and 40 patients in Group 2). Dilution of phenylephrine 5% and Tropicamide 0.8% mixture was applied to patients of Group A in both eyes and dilution of phenylephrine 2.5% and Tropicamide 0.4% mixture was applied to Group B patients in both eyes. Pupil diameter and pulse rate BP were measured and compared. Results: Mean age of Group 1 patients was 55.39 ± 11.47 and Group 2 was 49.95 ± 13.71. Among 36 males, 50% in Group 1 and 50% in Group 2 and among 45 females 51.1% in Group 1 and 48.9% in Group 2. Among both Group 1 and Group 2 patients, both left and right pupil size was significantly increased after application of dilutions, but there was more increase in the pupil size among Group 1 patients compared to Group 2 patients 15 min after and 30 min after application of drug. Conclusions: The combination of 0.8% tropicamide and 5% phenylephrine was effective compared to alternate application of 0.4% tropicamide and 2.5% phenylephrine for rapid and sustainable pupil dilatation for indirect ophthalmoscopy.