our 13yo lab is showing what the vet calls early canine cognitive dysfunction and im trying to decide between starting anipryl now or pushing supplements first, looking for people whove been through this decision

Murphy is 13.5, black lab, 78 pounds, our second dog and the love of my life. about 5 months ago we started noticing small things. he would stand in the corner of the kitchen for a minute before turning around. he started waking up at 3am and pacing for 20 minutes then going back to sleep. he forgot the cue to sit for his dinner bowl twice in a week, which had been bulletproof since he was 8 months old. nothing dramatic. just enough that my husband and i both noticed without saying anything to each other for a few weeks.

Took him to our regular vet in march. she did a senior workup, bloodwork was clean for a dog his age, no thyroid issue, kidneys fine, no obvious pain on exam. she said it looks like early CCDS (canine cognitive dysfunction syndrome) and walked us through options. her preferred starting point was selegiline (anipryl) at 0.5mg per kg once daily, with supplements as a layered support, and review in 8 weeks. she said the evidence is real but not dramatic, and that earlier intervention generally goes better than waiting.

What im stuck on. selegiline has potential interactions and side effects (we have him on a low dose of carprofen for hip arthritis and that combination needs monitoring), and im not sure i want to start adding medications to a 13 year old until i know we have tried the lower intervention things first. my mom in law had alzheimers and i watched what aggressive medication did to her quality of life in her last 18 months, and i know thats not a fair parallel but its in my head. on the other hand the vet was pretty clear that the evidence for "just supplements" being equivalent is weak and that we might lose months of effective intervention if we delay.

So my actual questions. one, for people whose senior dog was diagnosed with CCDS, did you start on selegiline early or did you try supplements (purina neurocare, hills b/d, fish oil, SAM-e) for a few months first, and looking back what would you do differently. two, what does the day to day look like a year or two after diagnosis if intervention is working, because i need to know what im trying to preserve. three, how did you balance "doing everything possible" with the reality that hes 13 and we probably have 18 to 30 months left no matter what, im not trying to extend his life im trying to make these months feel like the dog we know. and four, did anyone find a non drug intervention that actually mattered, like enrichment changes or sleep environment changes, because the vet listed those as "supportive" but i want to know if any of them moved the needle in real life