What Causes Constipation After Taking Trazodone?

After changing to trazadon and experiencing severe constipation, my energy level has bottomed out. I can have a good day including mowing the yard and working in my woodworking shop and then I will have a couple of bad days. I sometimes am in the bed all day. I am a 67 year old maintenance supervisor from a local paper mill and have always been very active. I was diagnosed with diabetes around 55years old. Also diagnosed with heart attack. An angiogram revealed no damage. I was diagnosed with micro cardiogrovascular desaese. An endoscopy revealed some ulcers. I was put on protonix and all chest pains have stopped. A complete bloodwork analysis showed only light vitiman defecienses. I have been taking vitimans but am still not doing well. My medicines are losartan, gabapenten, nortriptlyn for nuretopthy, restoril, fish oil, celexa, protonix, pravastatin.