There can be three rx plan. 1. Topical 2.Photo therapy 3.Oral medication. For topical usage corticosteroids are useful in this case.besides you can give vit D analogues, Vit A to reduce skin patches. Photo therapy will help a little also. Daily little amount to direct sun exposure can cure the skin as well and make them smooth. Orally you can prescribe MTX to reduce inflammation.. And to relief pain NSAIDs can help.. IV infliximab can also relief athralgia to some extent. Thats all i know. :)