Relistor is a relatively new drug for opioid-induced constipation. Movantik also treats this. Relistor is very expensive but you should be able to get it free if your income is limited. Check with your prescriber if an expensive drug is prescribed about this. I forget who they contact but I got one year of Relistor for free.

It works ok, I guess. Better than nothing. And then do the usual - fiber, water, exercise, prunes pr prune juice - maybe a laxative if you really need help.

All the best to you.