This post is a further postscript to
as someone who has been taking amitriptyline at night for more than a couple of years it's a good job that I thoroughly read the Patient Information Leaflet! To replace amitriptyline and a low dose of sertraline my GP has prescribed a drug (which I'm supposed to start immediately) which explicitly states that one "should not take Trazodone if I've taken amitriptylene within the last two weeks".
It also states special care should be taken if "your age is above 65years, as you may be more prone to side effects" and "take special care if you suffer from conditions like abdominal pain, muscle weakness, mental confusion"
I am 71yrs 7months of age, and suffer intermittently with abdominal pains and muscle weakness as part of my general state of unwell-being (ME). Even mental confusion was present not long after I first succumbed to ME at the end of 2003.