The author replies

Coiffard and Couteau have raised some pertinent queries.1 We are quite aware of the lipophilic nature of most lipstick pigments (not all, though),2 which is evident from the fact that our patient had been applying different brands of lipstick multiple times a day for many years without any change in the color of her urine.3 It was only with the introduction of a new brand of lipstick that her urine turned red, which she did not attribute to the change of lipstick because it had never happened before.
Source: Kidney International - Category: Urology & Nephrology Authors: Tags: Letter to the Editor Source Type: research