Question

how might a phosphodiesterase inhibitor affect your photoreceptors and your vision

Answer 1

Phosphodiesterase inhibitors specially Phosphodiesterase 5 (PDE5) inhibitor causes vasodilation of retina vessels due to disturbance in cGMP metabolism. Phosphodiesterase inhibitors inhibits phosphodiesterase 6 (PDE6) present in the photoreceptors (rods and cones) due to which there is mild and reversible visual changes like impairment in differentiating blue and green color. Due to phosphodiesterase inhibitors there is increased sensitivity to light in the photoreceptors. The color vision also may decrease and there can be blurred vision.