Scrampers appear in packs. Scrampers, like rothes, can cause a quick YASD if they attack together. (A group of 3 or 4 scrampers might even kill a fully-healed player in one turn.) Handle scrampers like rothes, with the same tactics.
Retreat into a corridor, to fight one against one. Let your pets help. Because scrampers are as slow as rothes, you can also do hit and run, make ranged attacks, or just run away. Engraving Elbereth can scare scrampers away from you.