Welcome to NeuroTalk.

It is quite possible it is the Paxil. Long term use of SSRIs affects dopamine and reduces it so there can be muscular effects.

Then there is the discontinuation syndrome on top of that when anyone discontinues an SSRI after long term use.

If he is looking to help correct this problem, there is an antidepressant, called Wellbutrin, which may increase dopamine.
(generic name is bupropion). It is not considered an SSRI.

Some people coming off SSRIs also try the amino acid tryptophan to help the body make more serotonin. Serotonin synthesis is actually reduced by SSRIs since they promote reuse of exisiting serotonin in the synapse of the nerves. So production of "new" is reduced. Going off SSRI then results in low serotonin activity until the body catches up and restarts production. You cannot use tryptophan if using another SSRI or SNRI drug substituted for the Paxil. So discuss this carefully with your doctor.

Itching comes with opiate therapy. Adding that for pain, may make the itching worse. Itching does not occur for everyone however. The antihistamine Atarax (hydroxyzine) is typically used for itching that is severe and all over the body.

Because of the liver involvement, Cymbalta is OUT... This drug causes liver damage and not indicated for anyone with liver issues. Some doctors don't know this yet, so be aware.

Restless legs sometimes responds to improving magnesium levels in the body. These may be low-- and this is common in US.

This is my magnesium information thread:
http://neurotalk.psychcentral.com/thread1138.html

With the history of liver disease, you will always have to be monitored carefully by a doctor, have testing done, and discuss any supplements you decide to try.

There are other forums on the web that are devoted to Paxil.
(angry patients etc.) just Google that.