Hi Justin, Welcome to the wacky world of posting on the JMDL where you risk becoming a Public Person with a single mouse click.
I don't remember the details about Joni's personal motivation at the time for the lines, "Doctor's pills give you brand-new ills." but certianly imperfect health is an ongoing theme in her life, most significantly when she was bedridden as a kid. If you don't know that story, check out the bio on www.jonimithcell.com first. The neat thing about her lyrics is that you can live inside a refrain for a time and live in another verse in another. What I mean is, the song is so true to the experience of Medicine that you have discovered the lyric for yourself. But anyway, back to your question. There are tons of articles on the www.jmdl.com site, built by Les Irwin of Colorado. If she talked about health problems in interviews for that album, you'll find the comments there. It's an amazing resource. Lama