Ocular toxicity of Afromomum melegueta (alligator pepper) on healthy Igbos of Nigeria.

Afromomum melegueta is an ubiquitous specie of the family Zingiberaecea. It is a very popular spice used mainly as food, in brewing, and in veterinary and traditional medicines. The effect of acute consumption of A. melegueta seeds on some visual parameters was studied with a view to determining the adverse ocular effects. Results showed that bolus consumption of 0.35 g of A. melegueta seeds by 10 healthy male Igbos age 30-35 and body weight 60-68 kg increased the near point of convergence (NPC) by 17.2% and reduced the amplitude of accommodation (AA) by 9.2% without affecting the pupil size and the visual acuity. The increased NPC leads to doubling of vision while the reduction or loss of accommodation would lead to blurring of vision both synergising to impair vision at least transiently. Non-specific mechanism of action or papaverine-like activity is suggested.