I would say the treatment is a LOT to mentally deal with.
I found the first 1/3 was okay and the middle bit uncomfortable (prob depends on how much gas you have etc), and the last bit was hard. I felt sick and cold, but I was reassured & I could ask for a blanket to make me feel better.
It isnt for the faint hearted, esp after my first session. I had a big headache and was worried about my 50 min journey home. I made it all okay. The 2nd session i was tired after but not as headachy as first1