These symptoms are being treated with what kind of medication? It is possible that even with thyroid medication, he's not getting enough of it. His symptoms are common to people with underactive thyroid levels and if you're not getting satisfaction with the current doctor, you need to find him a new one. And keep looking until you have someone willing to do a comlete workup on him. Not just for thyroid but other potential problems that can cause similar symptoms. Sometimes it's not easy to gauge if it's the thyroid or something else unless you rule everything else out first.

My blood labs all read normal when there was still a problem (growing goiter and more nodules) and I have a strong family history of "normal" readings but still a thyroid problem, especially with goiters and nodules. I ended up with a total thyroidectomy as a result of poor care when I should've been able to take thyroxine instead, as I had been with my previous endo until he decided to focus on diabetes research. I had a difficult time finding a good doctor who listened to me and my symptoms. Several dismissed me as being fine and it was something else though the labwork came back negative on it all. By the time I found a good endo who put me back on TSH Suppressin Therapy (what'd I'd originally been on), it was too late. Althought we tried it for six months, the goiter had grown too large and caused difficulty breathing and eating. I almost choked to death on a piece of meat once. Scary! I didn't have a choice but to have it removed in order to alievate the pressure in my neck.

Point to all that is you should keep at it and insist his doctor take care of him and find out what's wrong, thyroid or not. If he plays it down, find someone else. And keep finding someone until you find a doctor who won't dismiss your dad's symptoms.