Ocular dynamics of systemic aqueous extracts of Xylopia aethiopica (African guinea pepper) seeds on visually active volunteers

Xylopia aethiopica, African guinea pepper, is an angiosperm belonging to the family Annonecae, and used mainly as spice and in traditional medicine. The ocular dynamics of bolus consumption of 300mg total dose was undertaken on visually active volunteers with a view to finding its ocular effects or complications. Results showed that the aqueous extract of X. aethiopica was neither a miotic nor a mydriatic, but lowered the intraocular pressure (17.48%), reduced the near point of convergence (31.1%) and increased the amplitude of accommodation (8.98%) which are positively correlated (r=0.95). On the other hand, the systemic extract had no effect on the visual acuity at far and near as well as the phoria status at the appropriate distances. The convergence excess resulted in esophoria and the increased amplitude of accommodation placed greater demand on accommodation mechanism without any discomfort. The nonspecific mechanism of action makes it a safer spice which can be exploited in the management of exophoria and raised intraocular pressure (glaucoma) in instances where the efficacy of the older conventional drugs is insufficient. © 2002 Elsevier Science Ireland Ltd. All rights reserved.