I have a form called Psoriatic Arthritis, this is a problem with the surface of the joints and is an internal form of Psoriasis. It is very painful at times and I am being treated with a long list of drugs to help me keep in work.
I am taking Methotrexate, which is a cancer treatment and really zaps me at times, for the side effects from this I have to have 6 weekly blood and urine samps taken to measure all sorts of body functions including liver and iron etc, I have to have Folic acid and constant iron along with other tablets, I take Atenanol for high blood pressure and another for RLS which really bugs me (restless leg syndrom) I usually have to give up early in the evening and go to bed. with all of this I get very depressed and so take amatriptaline on a night and another different pill in the morning, I also have Osteo arthritis too but the problems with that are masked by my medication to a certain degree, I take Ibuprofen, co-codamol and Paracetamol to help with this.
I Know, it sounds like I'm a walking Pharmacy, but it does help and I manage to do my job as a school caretaker, although lots of walking is involved so I end up resting a lot.
My wife also suffers and has just recently had both her knees replaced with full joints.
There is a very good website for information on this topic, you will find lots of information here
http://www.arthritis.org/
Hope that helps, and you have my sympathy....
Pete