Which statement about mineral oil–based topical products is true?

• A. Mineral oil–based topical products appear to have minimal efficacy.
• B. Mineral oil–based topical products have strong efficacy.
• C. Mineral oil–based topical products were not studied.
• D. Mineral oil–based products cure evaporative dry eye.

Answer: (A)

Mineral oil–based tear substitutes mainly add a lipid layer to the tear film to reduce evaporation. In veterinary evaporative dry eye, this method often yields only modest relief and does not substantially alter the disease course; they do not address tear production or ocular surface inflammation as effectively as other therapies. Because of this, the statements about their efficacy tend to be understated—there isn’t strong, consistent evidence of high efficacy, and they are not cures. The idea that they cure evaporative dry eye is not supported, and while they’ve been studied to some extent, the best-supported takeaway is that their efficacy appears minimal overall.