I’m 70 and no longer get buzzed from THC and I’ve been a cannabis user for over 30 years. I use a 10:1 CBD:THC tincture 0.5ml 4x day, I use a 5:1 CBD:THC 0.5ml and a full strength THC 0.5ml at nighttime to sleep. I vape a CBD heavy cartridge with some THC (entourage effect is important) throughout the day or mini-dose so I can maintain my levels. I haven’t needed any breakthrough pain meds in months and I still have 1/2 my oxycodone prescription from Oct. 2021. Good luck with your pain but what are you worried about at 75 and getting buzzed? You only live once and you might enjoy it.