Besides having MG i also have RA and take methotrexate, folic acid and prednisone. Went to have a filling in lower side tooth, told the Dentist, only carbocaine no EPI...and he said fine. The first couple injections, didn't hurt to bad but then , It felt like he was giving the next two in my cheek the pain was excruciating. But here is the worst part. He finished Filling my tooth, and as time went on I was getting more and more numb, all my bottom gums, and teeth and my top gums and teeth, tongue, lips jaws, it took about4 hours to wear off., I was nauseated, and I was trying not to panic, as I could hardly swallow, it was terrible, I never had this happen before.I have to get another tooth filled I am so afraid.