Can a child just use reading glasses bought at a drug store?
No. A professional should be seen to obtain individualized advice. Drug store reading glasses are intended for adult-size heads. The distance between the lens centers conforms to the usual distance between the pupils of the adult head. If such glasses are used by young children, who have a smaller interpupillary distance, the “prismatic effect” of the lenses causes increased convergence. This can cause problems such as double vision and should be avoided. The distance between the child’s pupils should be measured when the eyes are converging on a book. The centers of the eyeglass lenses should not be any farther apart than that distance.
