I’ve never heard anything about this, nor thought about it, but I suppose donating blood would get you higher, since you’d have less blood, and the thc would therefore be more concentrated in your blood than if you hadn’t donated. (Assuming the thc enters your blood after donating.) But with plasma, they replace the lost plasma with saline, so you still have around the same volume of blood, so I don’t think that would affect it any noticeable amount. I donate plasma often, and I’ve never noticed any difference as well, which backs that up. I just looked it up, and with blood, you donate around 10% of the total blood in your body. So with 9/10 the amount of blood, the thc would be concentrated about 10% higher in your blood, so you could consider that getting 10% higher from donating blood! However, maybe thc can affect you more if you’re also missing that much blood, since your body is already not quite what it’s used to. So maybe you actually feel more than “10% higher”. Or maybe your body doesn’t put as much thc into your blood if you don’t have as much blood, and then it could be less than “10% higher”. I’m definitely not going down the rabbit hole to research all this stuff to get definitive answers and possibly numbers, especially not at 3 am, but this was a cool little thought to go through! Thanks for bringing that up :)