My Husband Is Taking Medication For Pain. He Is Having

My husband is taking medication for pain. He is having surgery soon but, until then he needs to take pain meds. He is having a problem urinating. He feels like he has to go but, cannot go. I think this is a side affect from the drug(s) he is taking temporarily. This same thing happened to him when he took these same medications one year ago (Gabapentin). He is taking colace for constipation. Will Colace also help him urinate? I think I recall someone at the hospital telling me that but, I cannot remember.. Tks..Marianne
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