I have a couple of friends that seem to struggle each time they go above 10,000 feet, so there certainly seems to be a strong genetic component.
I used to use Diamox but hate the side effects. I just started hyrdrating really well and using ibuprofen. I take anywhere from 2 – 8 OTC ibuprofen each day I’m 10K or higher. It is anecdotal I know, but some studies also suggest ibuprofen helps. I usually come from sea level as well, so I always try to stay in front of altitude sickness.