I Have Severe Burning In Mouth And Throat, Can Be

I have severe burning in mouth and throat, can be painful. I have had myasthenia Gravis, diagnosed in 2003. My symptoms are much improved but still get some weakness and double vision. I take cellcept and get IV Ig infusions every 8 weeks. Stopped Mestinon approx 2 years ago, have it for pen use which is infrequent. Saw ENT for the dry burning mouth yesterday. Pilocarpine 5 MG Rx given. Is it safe for me to taken this? I'm 63 and have been an RN for 38 years. Thanks

Not the first time I've had this. In 2006 ENT thought it was viral, accompanied by freq canker sores. Had the condition for 8-9 mins and spontaneously disappeared. Have had it occlly but not often since then, restarted 2 1/2 months ago. Mostly concerned if the drug is safe.