Fluorouracil for lip dysplasia?

My husband recently (late April) had a biopsy of his lower lip which had a white scaly patch from smoking and sun damage (he is a farmer and spends a lot of time outside). The report stated there was "mild epithelial dysplasia and hyperkeratosis" extending "to involve one of the lateral surgical margins of the specimen." The surgeon told him to make an appointment in 6 months.  His newly sensitive mouth has been tingling and burning, though he has worn lip protection constantly (and we are wondering if that contributes to the burning sensation since it is on the upper and lower lips both) so he went to get a second dermatologists opinion. The doctor prescribed flourouracil to apply to his lips for two weeks followed by an appointment. In reading the warnings on the prescription it says that it should not be used on the mucous membranes but it's going to get on them with application to his lips. The pharmacist - who said it will really hurt - raised his eyebrows and seemed surprised that the doctor did not give my husband more information about this chemo agent. Just said "put it on your lips." Does this sound like a reasonable move to you or should he see yet another doctor?

[Alan Rockoff, MD]

5-flourouracil can be irritating, but it can be used on the lips, under proper supervision.  Your husband might want to speak to the dermatologist who prescribed it to get more details about what to do if it gets too drying, as well to speak about alternative approaches (one of which is to do nothing and watch, as the first doctor suggested.)

Best.

Dr. Rockoff

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