Interceptor can be used to treat heart worms in dogs, treating heart worms in dogs too aggressively initially can lead to death therefore vets within the US require a prescription. Since most vets want to avoid any liability issues they are reluctant to provide a scrip for the drug.
I have gone to a vet and described the intended use of the medication for the treatment of RB and still been turned down.
Some Vets are more easy going and will give a script.
Interceptor targets Arthropods, anything that has an exoskeleton, pods, RB, crabs, shrimp........
Having used the drug twice for treatment for RB I find the drug to be benign to the tank in general except for those Arthropods listed above. Bristle worms and brittle stars looked stunned but recovered.
A secondary effect is pristine water clarity and absence of film algae for a couple weeks after treatment.
To avoid the death of crabs and shrimp you need to remove them prior to treatment or treat with lessor dose.