Zelnorm is approved for men and women, actually. It's Lotronex (which is a last-resort treatment for the opposite problem of chronic, severe diarrhea) that is generally used only in females. Did the blurriness just start when you tried Zelnorm?
A lot of members who suffer from constipation on this site take fiber supplements, increase their fiber intake, natural stool softeners, etc. but you may have already tried many of these. Do you exercise regularly? Sometimes a good jog or workout will get the bowels moving, in addition to a lot of soluble fiber (raw veggies and fruits, etc.)