Can having bad reflex sympathetic dystrophy qualify you to have a service dog?

Depends: Service dogs can be helpful in patients with severe anxiety. Since anxiety is a factor that causes increased pain in patients with rsd, it is helpful to control it by whatever means possible. Sometimes, this may mean a service dog.

Level of dysfunction: Having a particular diagnosis doesn't qualify you alone. It all depends on the level of functional impairment that is present given the type and severity of your symptom complex. You need to be evaluated by your physician or physiatry to determine your level of dysfunction to see if you qualify.