Patient with open angle glaucoma with 7D of myopia, complains of blurring of vision on administration of pilocarpine. What is the reason for the blurring?

Pilocarpine (1, 2, 4%: 3-4 times/day). It is a very effective drug and had remained as the sheet anchor in the medical management of POAG for a long time. However, presently it is not being preferred as the first drug of choice or even as second choice. It is because of the fact that in younger patients it causes problems due to spasm of accommodation and miosis. Most, but not all, older patients tolerate pilocarpine very well; however, axial lenticular opacities when present precludes its use in many such patients. Therefore, presently pilocarpine is being considered only as an adjunctive therapy where other combinations fail and as second choice in poor patients. Re : A K KHURANA OPHTALMOLOGY,E4,Page-222