Upon request my dentist sold me ($20) a tube of Fluoridex [1] prescription toothpaste with 1.1% sodium fluoride to use at night. The instructions are to avoid eating or drinking afterward for 30 minutes, which is easy when you are asleep.

The Colgate I use in the morning has 0.25% sodium fluoride for comparison, so the prescription toothpaste is 4x stronger.

There are some threads on /r/dentistry/ suggesting that SnF2 can cause irritation.

Whatever compound, the benefit of fluoride toothpaste is increased by not washing it away with a mouth rinse after brushing.

[1] https://dentalhealthessentials.com/fluoridex-sensitivity-rel...