So unless a condition is a) going to go away of its own accord (is self-limiting) and is something you can diagnose and treat successfully yourself, companies can't sell their nostrums over the counter. Or to put it another way, while it's conceivable that a homeopathic treatment might make something go away or get better more quickly, whatever disease or condition it's marketed for has to be one that will just kill itself off anyway.
The FDA also says "The labeling for those products offered for OTC retail sale must bear at least one major OTC indication for use ...", meaning that "You'll feel better!" or "Increase your quality of life!" don't cut it. The labeling has to tell you why you might actually want to
Recently, the FDA has had to send warning letters to at least six homeopathic marketers, reminding them of this.