According to the Annals of Rheumatic Disease, somewhere between 6 and 42 percent of people with psoriasis, a common skin condition involving scaly, itchy rashes, also have a serious joint disease called psoriatic arthritis. Psoriatic arthritis is an autoimmune disease in which the body’s natural defenses against infection attack its own tissues instead, causing damage, pain and swelling.

As with other inflammatory forms of arthritis like rheumatoid arthritis (RA), people with psoriatic arthritis may experience flares, periods of intense disease activity when symptoms are at their worst.

Psoriatic arthritis can affect joints and various parts of the body. It commonly affects the heel (Achilles tendonitis) and the bottom of the foot (plantar fasciitis). 

The joints of the fingers and toes often swell up creating a "sausage effect," in which the finger or toe is swollen along its full length, a condition called dactylitis. It's common for the lower back at the sacroiliac joint to be stiff and painful.

Painful spots are sometimes not precisely at the joint. The places where tendons and ligaments attach to bones can become inflammed and painful. Those spots are called entheses, and the inflammation is enthesitis.

The pain, fatigue, swelling and difficulty using joints may that result from this condition may limit the ability to participate in daily activities.

Accurate diagnosis and early, aggressive treatment of psoriatic arthritis are important. In PsA, the immune system, which normally protects the body, goes awry. It causes inflammation that if not properly treated, over time can lead to deterioration in joints and the structures (muscles, tendons and ligaments) that support them. Luckily, there are a number of treatments, both over-the-counter (OTC) and prescription, available. Some treat symptoms of both psoriasis and psoriatic arthritis and others control, or modify, the disease by disrupting runaway inflammatory chemicals. In addition, there are many self-care strategies you can use to manage your symptoms and feel better overall.

Medications for Psoriatic Arthritis

NSAIDs: Nonsteroidal anti-inflammatory drugs (NSAIDs) are usually taken by mouth, although some are available in topical form. They reduce inflammation along with the pain and swelling that accompanies it. Among the most well known over-the-counter NSAIDs are ibuprofen (Advil, Motrin, Nuprin) and naproxen sodium (Aleve), although there are many others. Plus, there are more than a dozen prescription NSAIDs available. The most notable risks of NSAIDs are heart attack and stroke, along with stomach irritation and bleeding that could become severe.

Corticosteroids: These drugs are designed to mimic the anti-inflammation hormone cortisol, which is normally produced by the body’s adrenal glands. Prednisone, taken orally, can help reduce inflammation in the short term, but long-term can lead to side effects such as facial swelling and weight gain. Directly injecting corticosteroids into affected joints can provide temporary inflammation relief.

DMARDs: The disease-modifying anti-rheumatic drugs (DMARDs) are a varied group of medications that suppress inflammation-causing chemicals to prevent joint damage and reduce symptoms. They are mostly oral drugs. According to the American College of Rheumatology, the DMARDs most commonly prescribed for psoriatic arthritis are sulfasalazine (Azulfidine), methotrexate (Rheumatrex, Trexall), cyclosporine (Neoral, Sandimmune) and leflunomide (Arava). Azathioprine (Azasan, Imuran) may also be prescribed.

Apremilast (Otezla), a new oral drug approved in 2014, is a new type of small-molecule drug that has a unique mechanism -- inhibition of phosphodiesterase 4 (PDE4). Blocking PDE4, an enzyme involved in inflammation, has been shown in manufacturer studies to reduce the number of tender and swollen joints. 

Biologics: This subset of DMARDs are large molecule drugs, given by injection or infusion, that stop inflammation at the cellular level. There are two types of biologics approved to treat psoriatic arthritis. The first type suppresses tumor necrosis factor alpha (TNF-alpha), a specific protein produced by immune cells that signals other cells to start the inflammatory process. These include etanercept (Enbrel), adalimumab (Humira) and golimumab (Simponi), which are given by injection, and infliximab (Remicade) and another version of golimumab (Simponi Aria), which are given by infusion in a doctor’s office. The second type of biologic is an interleukin-inhibitor that was approved to treat psoriatic arthritis in 2013. It is an injectible therapy called ustekinumab (Stelara). Another injectable TNF blocker called certolizumab (Cimzia) was also approved to treat psoriatic arthritis in 2013. While biologics can be very effective, they suppress the immune system and raise the risk of infections.