Every once in a while, about the time that my Sinemet should be kicking in, I'll get a tightness in the thoracic area of my spine and into my shoulder blades. It's very similar to the pain you get when you swallow wrong or get something hung in your esophagus. It lasts for about 5 minutes, and goes away completely.
Oddly enough, this pain occurs most when I'm driving after taking my Sinemet. No idea what the correlation is, unless it's the sitting position/arm movement triggering it.
Not sure if this is a form of dystonia or not. I used to get similar pain before diagnosis that I thought was a hiatal hernia, but that always came on immediately after ingestion of food, not 30-45 minutes later.
Does anyone else get something like this?