Yes, hydrocodone can cause constipation, even after you've been taking it with no problems for awhile. Opiates slow the digestive tract. I've been taking hydrocodone (Vicodin) for chronic pain too. On the days when I take less, I have much better BM's. The days when I need more, I end up getting stopped up. I think as long as you need the opiates for your chronic pain, you'll need to counteract the constipation with another medication. Ask your doctor if you can take peri-colace safely, along with your pain meds. After I had surgery in January...I took two peri-colace (generic brand) every night and it seemed to keep things moving while I was on much higher doses of pain meds.