<prompt> Aldose reductase inhibitor drugs are useful inCataractDiabetes mellitusHereditary fructose intoleranceEssential fructosuria  <response>: Ans. is b i.e., Diabetes mellitus Aldose reductase catalyzes the NADPH-dependent conversion of glucose to sorbitol, the first step in polyol pathway of glucose metabolism. Aldose reductase inhibitors are a class of drugs being studied as a way to prevent eye and nerve damage in people with diabetes mellitus. Examples of aldose reductase inhibitors include: Tolrestat withdrawn from market Apalrestat Ranirestat Fidarestat 