Dreamer, you're absolutely right about the alcohol, and it all comes under the general heading of "independence". Even when his brain has the blood flow to be capable of being logical, it's not logical on this issue.
... that your father started on hydrochlorothiazide about 18 months before the mental confusion and forgetfulness started. One of the side effects of hydrochlorothiazide is "confusion", and the incidence of side effects may be increased by alcohol.
Your father has more problems than "confusion", but the hydrochlorothiazide might be contributing to his mental difficulties.
I'm not a doctor, and I only just googled "hydrochlorothiazide side effects"...but it might be worth asking a real doctor about drug interactions.
I am still uncertain on how it will play out but thanks Nords and others for taking the time to share your experiences.
One of the reasons I lay this personal stuff out on websites to (mostly) total strangers is because you keep coming up with good suggestions. I read the prescription "side effects" labels and printouts but none of them mentioned this!
When he went on BP meds they tried several before settling on these two. He was hammered pretty hard with all of the side effects and almost didn't complete the process. His description of the weeks of testing was pretty brutal, and I can see why he's burned out on doctors.
Thanks, everyone. I'm adding it all to the list of things to keep mentioning to him as well as to my brother, and perhaps someday having a conversation with Dad's doctor.
I should point out that when this guy was in his 30s he had all of his wisdom teeth removed on the same day because it was more efficient. On a Friday because he could leave work early. He didn't realize that when the painkillers wore off he wouldn't be able to get a prescription until Monday. Later he joked that he couldn't even grit his teeth (engineer humor).
This is also the guy who, as a widower in his 60s, waved off all filial offers of companionship & help for his prostatectomy. He even took taxicabs to & from the hospital.
When spouse and I have these conversations she rolls her eyes and says "Gee, honey, good thing you're not like that."
One of the challenges of reaching an advanced age is that your friends are failing too. Does he have any friends who you trust to visit him or take him out from time to time, even if you pay them 'under the table'.
His LTC insurance may have an in-home care option that could be used if you could document his need for assistance. It will require a MD's certification so if he hasn't seen a MD in a while you will end up waiting until he is hospitalized.. the LTC waiting period would start then. Also, the visitor can document your father's needs which can help physicians assess his situation. If your Dad is a contrary cuss you can tell him that just because he sees a MD doesn't mean that he has to take his advice. The choice is his. You would just like him to visit the doctor so that if something serious happens there is a physician who can check up on the hospital.
IMHO the one aspect of aging that men have difficulty coping with is dependency. I have a former widower-colleague who used a Smith & Wesson when he realized that he was failing. Most LTC facilities prohibit residents from having a gun for just that reason.
My Dad sees "friends" as an intrusion and a burden. He may be a hermit but he's content in that lifestyle. And yes, that makes him very hard to keep tabs on if someday he doesn't answer his phone.
His LTC policy kicks in wherever he is, after some sort of waiting period, when a doctor certifies that he's unable to accomplish at least two of the activities of daily living. I understand that's pretty typical. Finances appear to be the least of our worries here.
Spouse jokes about her 9mm healthcare plan, but a sad fact is that a lot of old folks are lousy shots. And among my Dad's alcohol, the winter's icy sidewalks, the brutal cold, his driving, and his hiking the Rockies by himself... it's pretty easy to worry.