I bathe my ratties with a mild soap meant for human infants ..aveeno or some other product, with little or no fragrance. Get the one that has the most natural ingredients in it, by all means. When bathing, don't get any water or soap on their little face or in their ears ..as little as possible, if any.

Bathing will help with initial relief, but you still need to treat them for the bugs. Revolution is a good remedy that you can get from your Vet. It's made for kittens, so it is formulated correctly for the size/weight of your ratties, too. Ivermectin is also used, but it is tricky to get the right dose ...which is also risky!

Good Luck!