Pupillary changes among Nigerian adults following the instillation of Garcinia kola nut extracts: multicentric studies

BACKGROUND: A multi-centre, open, within-patient controlled study was performed on 106 adult volunteers to investigate the effects of Garcinia kolanut extracts on the pupillary sizes. STUDY DESIGN: 106 participants in three Nigerian Ophthalmic Centres with no pupillary defects and associated ocular or systemic co-morbidities had their pupillary diameters measured at 0, 15, 30 and 45 minutes respectively with a pupillometer (Neuroptics model # 586009). Using the left eyes as control, Garcinia kolanut extract was instilled into the right eyes at 15 minutes intervals. RESULTS: There were 63 females and 43 males ranging in age from 18 to 58 years with the mean age of 34.9 years. Average pupillary diameter measured among participants was 4.1 - 8.4 mm with the mean value of 6.0 mm prior to garcinia kola nut extract instillation. There was a gradual reduction in the baseline pupillary size with age in years at 0.2mm per decade without garcinia extract instillation. There was a significant higher baseline pupillary diameter in males than females with males and females mean values of 6.29mm (6.00 - 6.56mm) and 5.85mm (5.60 - 6.11mm) in the right eye (p=0.026) and mean pupillary diameters 6.16mm (5.90 - 6.42mm) and 5.80mm (5.56 - 6.04mm) in the left eyes (p=0.05) respectively. There were consistent significant miosis in the right eyes with instilled Garcinia kola nut extract compared to the left eyes at 15, 30 and 45 minutes (p=0.0000). CONCLUSION: 4% Garcinia kola nut extract drop has a transient miotic effect on human pupils not sustainable for more than 45 minutes.