Tolak Ointment

Look up the ingredients (active one is fluorouracil) and see what they do. www.google.com/search?client=firefox-b-d&q=ingredients+of+Tolak+Ointment

It says fluorouracil inhibits the growth of dodgy pre-cancerous cells in solar keratosis or similar. Topical side effects: Include severe redness, swelling, burning, stinging, and crusting at the application site as the abnormal cells break down, but the area heals completely a short while after the treatment stops.
www.google.com/search?client=firefox-b-d&q=fluorouracil

Ask you doctor or pharmacist to reassure you if it sounds scary.

I haven't heard of this brand name but my husband was prescribed a cream by the Dermatology Consultant to use on a suspicious mark on his ear. It seemed to redden the skin which then crusts and scabs over, which is normal.
Looking at the description, it is similar to Tolak cream.

However, when he was given a second prescription he was unable to find the cream anywhere; pharmacists said it wasn't discontinued but 'out of stock'.