You have to stop taking so much hydrocodone. You WILL kill yourself. Your body cannot handle all the acetaminophen that you are putting into it. You are destroying your liver and kidneys and you'd better hope it isn't too late already for you. How long have you been taking so many pills? Do some research, I did, and it scared me to death.
10g, or 10,000mg of acetaminophen is an acute overdose. It can kill you. Even taking that much over the course of 24 hours can be deadly for some people. When you take 20 of those pills, you're putting over 12g of acetaminophen in your body. You are doing that every day. I have no doubt in my mind that your liver and kidneys are damaged, possibly beyond repair by now, and it is only a matter of time and luck before you wind up in the hospital with that kind of habit. I know, because I did it, I'm an addict that just recently seen the light and I know how dangerous acetaminophen is. I'll say it again, you are going to kill yourself with that much intake. Get it through your head, the hydrocodone addiction itself, on it's face, is the least of your worries right now. The acetaminophen should scare the ***** out of you right now if you understood what I was talking about.
Get yourself to a doctor ASAP, I'm not kidding, and get your liver and kidney functions tested. Tell the doctor exactly what you've been taking and for how long. You won't get into any trouble, trust me.
As far as getting off the drug, there are many options. Methadone, is a good one since you also have cronic pain, as I do. Suboxone will also get you off the narcotic without the withdrawals.
I've quit a 20+ pills a day habit cold turkey, once, and it is the hardest thing I have ever done, and I only did it because I ran out of pills. It was 3 days of hell. The cramps you get is the acetaminophen destroying your body and small intestines. It binds to them. Read up on it, please. I gaurantee it will be enough to scare you straight. People really DIE from this all the time.