I was started on PTU 50 mg 3 times daily. I thought that this was a maintenance dose. My doctor feels this is the correct dose to start with according to recommendations from Endocrinologists he has talked to in the past. I am not so sure. Last night I started to develop a painful, swollen lymph node on the back of my left neck. Today all of my lymph nodes in the back and front of my neck are enlarged and painful. I feel like I am more sick. Is this a secondary infection or a side effect of the PTU? I am becoming frustrated.