Yeah, as harperfan7 said, the Black Crawler is a special Crawler "boss". The ones that come in groups and tag you with Hyperallergenic are Death Stalkers.
If you know ahead of time at all that you're going to be facing them, try taking an Irongut - it'll cut down the damage you take from Hyperallergenic to about 20 so you can afford to pop antidotes and advanced health stims, if you aren't all set from a regen vest and - if combat allows it - the bandages Hulk is so fond of suggesting
Failing that, back yourself into a corner or against a wall, throw down bear traps around yourself in a layer 2 deep, then toss a cheap frag or HE to make a ruckus. They'll come looking for the sound, see you, and charge right into the traps. Get your exterminator on.