Yes I need to take B-12 liquid orally or by shot, but my grandfather had pernicious anemia and it's hereditary, so I don't know whose fault it is. Other than that I have no major health problems, but I have neuropathic nerve pains that the doctor has never seen before so he blames the nitrous. It's not too bad. I was aware that I needed to take a lot of B-12 at the time. People ask me why I didn't get a tank instead of spending all the money on whippets. Because I would have died with a tank.
Two more cautions. Nitrous is an oxidant. I found out the hard way when I almost set myself on fire smoking and doing nitrous. Also, that whah whah you feel when inhaling is not nitrous. That's hypoxia which can cause serious brain damage. I learned to do nitrous in a continuous stream without the hypoxia like at the dentist office.
Edit: I remembered a third caution: nitrous is a hypnotic like kratom. You lose control, like an alcoholic or benzos blackout. One time after doing a bunch of kratom I "came to" riding my bike in my underwear at 2 am thinking I was going to find a swimming pool to take a swim. Fun times.