Here in "Baldknobber Land" we may not know much about Humira or Enberel or a dozen other "TNF Inhibitors", but we sure as hell know a lot about "inflamation".  Juist spending a few minutes watching the Walmart or McDonald parking lots will make it painfully clear that swollen joints, constricted mobility, stiff backs, aching knees, Irritable Bowel Syndrom, Asthma, and Arthritis, all flourish in our sore neck of the woods.   We do Ben Gay, Ibuprofin, TENS Gadgets, Hot Tubs, and Magnetic Bracelets.  What is causing all of this suffering?  Broadly speaking, we have no idea; we just accept that it's a part of life. Yes, you could ask your NP (we rarely see DR's accept for Cancer/Structural/Surgery causes), but she will most likely offer only some outdated antedotal nonsense and offer you a script for an expensive "new wonder drug" that she has no idea about t's path of action.
     So  who among us knows why so many of us feel like shit?   Probably no one with certainty, but the smart science kids working for Big Drug Companies believe they do.  They have found some pretty good evidence that a major cause is TNF. They are now getting rich because of this discovery. If your interested in the particulars.......... a simplified summary is that:
       Our bodies come equiped with "immune systems" that protect us from lots of things that can hurt us.  Our sub-conscious brain (operating system) detects when we are being attacked and send out various chemicals (medic-proteins) to neutralize the attackers.  One of the chemicals specializes in neutralizing Tumor Cells.  You see, our body is always making new cells and occasionally the copying process gets screwed up and a bad cell comes to be.  Our immune system detects this error and sends a protein to kill it before it harms the body.  Science guys have named this particular protein TNF, which stands for Tumor Necrosis Factor or Tumor Death Factor.  So far, so good, but as it turns out, this TNF chemical has a tough side effect; it causes inflamation.  This inflamation leads to all of the "we be sore and stiff"  symptoms refered to above.  Well you can probably guess what follows.  Yes, the smart science kids found, or made, another chemical that will neutralize the TNF.  They named this TNF Inhibitor, and of course it too has some ominous side-effects like increasing the chances of getting Cancer, and reducing the strength of your immune system, causing heart attacks, and on and on.
    So, do  you want to experiment with one of these synthetic protein cocktail like Humira or Enberal.   I guess, if your hurting badly enough, the answer is yes.  Americans, to the tune of $5 Billion a year, are saying yes.   However, if you do say yes,  please, don't be calling your Malpractice Lawyer when the class-action lawsuit ads starts showing up on cable.  Just accept that you understood and embraced the trade-off!