Psoriatic arthritis: pharmacotherapy update.

Psoriatic arthritis is a systemic disorder that causes chronic pain, altered physical appearance, and loss of function. The clinical features are diverse, but the core manifestations are psoriasis, peripheral arthritis, axial disease, enthesitis, and dactylitis. Our understanding about the psoriatic arthritis disease state, assessment, and treatment has advanced thanks to significant collaborative efforts by rheumatologists and dermatologists in the development of classification criteria, outcome measures to assess the various clinical domains, and treatment trials with agents also used for diseases such as rheumatoid arthritis and psoriasis. In particular, biologic agents, especially anti-tumor necrosis factor agents, have demonstrated significant efficacy and reasonable safety in all clinical domains of the disease, resulting in amelioration of clinical symptoms, inhibition of structural damage, and improvement in function and quality of life.