In a child with aniridia and glaucoma, a beta-receptor blocking drug was used in combination with Latanoprost. This was done because other combinations of antiglaucoma eyedrops had an insufficient pressure-reducing effect. It was very effective in reducing the pressure. However, there was a side effect: heavy sweat secretion over the entire body occurred 1-2 h after the application of Latanoprost drops. This side effect has not been described previously, and it indicates a systemic side effect of Latanoprost eyedrops. The systemic side effects of this substance are stronger then heretofore assumed, even in the case of proper local application. Therefore, one should be particularly careful in utilizing this substance, especially in children.