Is it normal to have cataplexy when in withdrawal from ephedrine (ephedrine sulfate)?

W/d from anticataple. Yes. Any anticataplectic agent when withdrawn can cause rebound cataplexy.
No. Firstly, stimulants do not really have a withdrawal syndrome in the way alcohol or opiates do. There may be a "crash" when people are no longer under it's influence, with a great deal of fatigue and lethargy sometimes. But I have never heard or read of cataplexy -- without knowing exactly your symptoms, i don't know if its really cataplexy. You should see a neurologist or your primary care dr.