Yes, I've tried Amitiza - and finally - something works! I am age 71 and I had gotten into a somewhat depressed state because of dealing with this situation for so long (mostly for several decades- but getting increasingly worse).
I use it in conjuction with Glycolax and for the first time in many exhausting, frustrating and painful years, I feel like I can know complete relief. I seem to need both medications for this to work for me.
Recently I had to go off of iron pills for chronic anemia because it was thought that they contributed to the constipation problem. So I had been taking a treatment where you take Iron in an IV form (over a period of 2+ hours). But now I'm wondering if the iron pills were really affecting my constipation problems, because after getting off the pills and going the IV route, I still had the same big problem.
The only side effects I've had are some occasional rumbling and grumbling, especially in the lower left side, some gassiness and urgency when I do need to go, but I would take that over what I was dealing with anytime. I've had no headaches, nausea or heartburn so far and I've been on Amitiza for about a month or so. I had tried it briefly several months ago, but it didn't work for me then. I don't think they "try" was long enough and I had stopped using my other helps for my severe constipation. I was down to the possibilty of having to go to the ER with my problem, and I was so dreading having to do that - so I somehow managed to take care of it at home, with some bleeding from hemorrhoids, much frustration, crying and disgust about it all. If I had gone to the ER it would have been a regular thing, because as soon as I got myself emptied, the whole problem just started all over again, and I was in the same mess in a couple of days. I have had a stent installed in a heart artery and thought all that extreme straining could not possibly be good for my heart.
So far, I am very pleased with the relief that this medication has given me and I can plan my life better around this problem that just wouldn't give an inch. Some people seem to think that the effectiveness reduces after a while, but I will take what I can get for now, and hope it continues.