Treatment of psoriatic arthritis (PA) can involve medication, patient education, physical therapy and occupational therapy. A physician is likely to prescribe a combination of medications. Some of these medications are designed to treat arthritis, others to treat psoriasis.

Medications used to treat PA include:

• Nonsteroidal anti-inflammatory drugs (NSAIDs). These include aspirin, ibuprofen and naproxen, which can help control pain, swelling and morning stiffness. NSAIDs are available in over-the-counter and in prescription formulations such as COX-2 inhibitors. In some patients, NSAIDs may cause stomach upset. They generally do not help psoriasis, and some may even make skin problems worse.
  
  
• Disease-modifying antirheumatic drugs (DMARDs). Reduce pain and inflammation while also helping to limit the amount of joint damage that occurs in PA. These drugs act slowly, and their effects may not be noticed for weeks or even months.
  
  Gold salts, a class of DMARDs, are sometimes used to treat PA but less frequently than in the past. This is because they may make psoriasis worse in some people and can damage the kidneys and bone marrow.

  • Corticosteroids. Medications that reduce inflammation and slow joint damage. Injection of corticosteroids directly into the joint can be useful for treatment of a few joints. However, corticosteroids usually are not recommended for long-term treatment of PA, because long-term use can make them less effective and cause serious side effects, including easy bruising, thinning bones (osteoporosis), cataracts, glaucoma, diabetes, high blood pressure and a decrease in resistance to infection. In addition, some patients who stop therapy aggravate skin symptoms and even trigger pustular psoriasis, a severe form of the disease.
    
    
  • Other immunosuppressants. Suppress the immune system, which mistakenly attacks healthy tissue in people with PA. Immunosuppressants include biological response modifiers (BRMs) such as tumor necrosis factor (TNF) inhibitors. TNF inhibitors block an immune system protein called tumor necrosis factor. This protein acts as an inflammatory agent in some types of arthritis. TNF blockers may slow structural damage to joints caused by PA. Side effects of immunosuppressives include increased risk of serious infections such as tuberculosis.
    
    
  • Retinoids. Synthetic derivatives of vitamin A that may be prescribed for psoriasis or PA.
    
    
  • Antimalarial drugs. Sometimes used to treat arthritis, but may cause flare-ups of psoriasis in people with PA.

  Arthritis also may be treated with physical therapy, exercise therapy and occupational therapy, as well as treatments such as thermotherapy, massage therapy and transcutaneous electrical nerve stimulation (TENS), a form of electrical therapy.

  Medications that may be used to treat mild forms of psoriasis include the following creams and ointments:

  • Coal tar. Likely the oldest treatment for psoriasis, it is a thick, black byproduct of the manufacture of gas and coke. Exactly how it works is not known, but it is effective for all forms of the disease except the severe generalized pustular types.
    
    
  • Anthralin. Normalizes DNA activity in skin cells and reduces inflammation. However, it can also irritate healthy skin and stain skin, clothing and bedding.
    
    
  • Vitamin D analogues. Synthetic forms of vitamin D that reduce skin inflammation and help prevent skin cells from proliferating.
    
    
  • Regular moisturizing creams. These can prevent skin dryness that accompanies many forms of psoriasis therapy.

  Oral medications may be used to slow cell growth and suppress the immune system. In addition, psoriasis may be treated with phototherapy. This uses natural or artificial light to suppress the growth of skin cells. It is usually reserved for severe psoriasis, as it may increase the long–term risk of skin cancer.

  Arthroscopy and synovectomy (removal of a joint's synovial membrane) have been effective in some patients with synovial or cartilage damage. In rare cases, joint replacement surgery (arthroplasty), typically involving the hip, knee or hand, may be performed if PA has significantly impaired joint functioning. However, few studies have been performed on the long-term outcomes. The chance that surgery becomes necessary appears to depend on how long a patient has the disease.