Insomnia Support Group
Insomnia is a symptom, rather than a disease, and is characterized by inadequate quantity or quality of sleep. People with insomnia complain of difficulty falling or staying asleep, which results in significant impairment of daytime functioning. Insomnia is categorized as transient (shorter than one week), short-term (one to three weeks) or chronic (longer than three...
If you're not getting anywhere with a GP you might ask for a referral to a doc that specializes in sleep.
Good that you're aware of the overlap of primary insomnia (no medical basis) with your OSA. Primary insomnia is far more prevalent, affecting pretty much half the population at one time or another.
One thing you didn't mention trying is CBT -- cognitive behavioral therapy specifically designed for insomnia. CBT sleep training methods are usually the first thing docs recommend. They are drug free and help most people who try them. That's what I used and it really helped me.
What I like about CBT is it enables you to comprehensively address the true roots of primary insomnia, which for most of us are some combination bad sleep habits and excessive worry about the idea of sleep. Treat those, and sleep tends to naturally improve on its own with no drugs needed.
As someone currently on Amitriptyline, and for whom it's only started to work recently, I have a few questions:
1.) How long have you been on it?
2.) What dose and dose schedule does your doctor have you on?
A few things about Amitriptyline I learned...When and how much you take means a lot! It had no effect on me until I hit 60 mg. My doctor prescribed 90 10 mg pills and said take 1 a day and keep adding another per day until you sleep or reach 100 mg. Like I said, at 60 (and especially 70-75) it's worked. I've got a few restful sleeps and it's taken away the fog, headache, etc.
Also, you need to be taking it about 3-4 hours BEFORE you go to bed. It is not a bedtime pill like a benzo. Several insomniacs told me that trick and it's helped. With Amitriptyline you still may not feel sleepy...But once you hit the right dose you'll magically somehow just sleep.
P.S. CBT therapy may help you too, especially if this is due to anxiety.