Has your husband looked at his diet and made proper dietary changes? Eating more fiber rich-foods and drinking plenty of water. I find a glass of hot water in the mornings before eating anything else is helpful. Also is there any one on the base that does acupuncture? I know a few people that have used acupuncture to get their bowel movments going again. I did come across something on a website that you can look at but if you are on a base, i'm not so sure if you can get the help.
Look at the constipation case. They have other stuff on this site but I think the best is to spend some time eating a healthy diet and have your body regain those signals. Taking a stool softener is also just a bandage approach but should give some immediate relief. If you take any fibre supplement, make sure you drink a full glass of water right after. This made a huge difference for me.