Psoriasis is a common skin condition where people have a buildup of rough, dry, dead skin cells. They look like raised, reddish-pink areas covered with silvery scales and red borders.

Psoriasis usually occurs on the scalp, elbows, knees, groin, and lower back. It is a long-lasting or chronic disease that "comes and goes," and may show up as a few spots, or involve large areas. It is not contagious. You cannot spread it from one part of your body to another, or from person to person.

More than 6 million people in the United States have psoriasis. You can develop psoriasis at any age, though it tends to come on during adolescence and old age. It usually comes on gradually, in both men and women. Doctors think psoriasis may be an inherited disease that can be triggered by emotional stress.

Most cases are not painful, although severe ones can be. About 5% of people with psoriasis also get psoriatic arthritis, a serious condition that involves painful and swollen joints.

The following are symptoms of psoriasis:

• Raised skin lesions, deep pink with red borders, and silvery surface scales. The skin may be cracked and painful in severe cases.
• Blisters oozing with pus, which usually show up on the palms or soles of the feet
• Pitted, discolored, and thickened fingernails or toenails
• Itchy skin in some people
• Joint pain from psoriatic arthritis, in some people
• Insulin resistance

Researchers do not know what causes psoriasis. They do know that people who have it make more skin cells than normal. A faulty immune system seems to be involved. In people with psoriasis, T-cells (a kind of white blood cell) mistakenly attack skin cells. The new skin cells move to the outer layer of the skin too quickly, where they build up and form thick patches.

There seems to be a genetic component. You are more likely to develop psoriasis if a close relative also has the condition. Several underlying factors may trigger the condition or flare ups, including:

• Emotional stress
• Obesity
• Skin injuries or sunburn
• Streptococcal (strep) infection, with symptoms sometimes appearing 2 weeks after strep throat
• Cold or dry air
• Certain drugs, such as gold, lithium, or beta-blockers
• Heavy alcohol use or smoking

Your doctor will examine your skin and ask questions about your physical and emotional health. You may need a blood test to check levels of calcium, zinc, and certain other elements, and a skin biopsy to confirm the diagnosis.

Your doctor may suggest one or several different treatment options, including:

• Creams and lotions for your skin
• Medications
• Phototherapy, or ultraviolet light therapy
• Changes in your diet
• Vitamin or mineral supplements
• Exercise

Drug Therapies

Prescription

Creams for your skin include:

• Corticosteroids. Reduce inflammation, often prescribed for mild-to-moderate psoriasis.
• Salicylic acid. Helps slough off dead skin cells. May be used along with other creams or coal tar.
• Retinoids, drugs made from vitamin A. Tazarotene (Tazorac) helps control symptoms by slowing down how fast skin cells grow and are shed. Tazorac is often used with a corticosteroid and light therapy. Women who are pregnant or plan to become pregnant within 3 years should not use it.
• Calcipotriene (Dovonex). A kind of synthetic vitamin D3 that slows down the rate of skin cell growth. May be used by itself or with other creams or light therapy.

Systemic drugs, used for more severe symptoms, are taken by mouth, injection, or infusion. All may have serious side effects when used for a long time. They include:

• Methotrexate. Helps block the growth of skin cells and reduce inflammation. May also be used to treat psoriatic arthritis. Studies suggest that taking methotrexate may reduce the risk of cardiovascular disease. Using it for a long time can cause serious side effects. Your doctor will monitor you.
• Cyclosporine. Suppresses a faulty immune system.
• Oral retinoids. Acitretin (Soriatane) slows down the production of skin cells. Symptoms may come back after you stop taking this medication. It can cause severe birth defects. Women must not get pregnant for at least 3 years after taking it.

Biologics. Help suppress overactive parts of the immune system. These drugs may be given when traditional drugs don't work, or when someone has psoriatic arthritis. They are given by injection or infusion (IV), and include:

• Alefacept (Amevive)
• Etanercept (Enbrel)
• Infliximab (Remicade)
• Ustekinumab (Stelara)
• Adalimumab (Humira)

Over-the-Counter

• Nonsteroidal anti-inflammatory drugs (NSAIDs). Reduce inflammation and pain, especially for psoriatic arthritis. NSAIDs include ibuprofen (Advil, Motrin) and naproxen (Aleve).
• Petroleum jelly. Softens skin, helps it retain moisture.
• Coal tar ointments and shampoos. Relieve symptoms. Help light therapy to work better.
• Capsaicin cream. For pain and inflammation relief. May reduce redness and scaling. Main side effect is a brief burning sensation.

Phototherapy (Light Therapy)

One of the treatments for psoriasis involves ultraviolet light. Some people may get relief from symptoms through brief exposure to sunlight each day. Too much sun can make symptoms worse. So your doctor will need to set up a treatment program for you. Be sure to wear sunscreen with an SPF of 15 or higher and avoid sunburn. Artificial ultraviolet light may also be used, often along with medications, under your doctor's supervision.

Complementary and Alternative Therapies

Mind-body therapies and stress management, including meditation and hypnosis, may help treat psoriasis. Studies show that people who practice meditation before getting light therapy do better than people who had light therapy alone. Exercise can help, too, as can drinking plenty of water.

Taking daily baths with lukewarm water and mild soap can help slough off scales. After your bath, gently pat skin dry and immediately apply a moisturizer to seal in water.

Talk to your doctor before taking any supplements or herbs, because some can have serious side effects or interact with common prescription medications, such as blood thinners and birth control pills. If you are pregnant or breastfeeding, ask your doctor before taking any supplement, herb, or over-the-counter medication. Be sure all your health care providers know about all therapies you use, including complementary and alternative therapies.

Nutrition and Supplements

• Avoid alcohol, simple sugars, and foods high in saturated fats. A gluten-free diet may help improve symptoms. If your doctor suspects food allergies, he may recommend an elimination diet or food allergy testing.
• Fish oil. Studies are mixed about whether fish oil can help relieve psoriasis symptoms. One study found fish oil reduced itching, redness, and scaling but did not reduce the size of skin lesions. Other studies found fish oil was no better than placebo. If you want to try fish oil, talk to your doctor before taking a high dose. Fish oil can increase the risk of bleeding, particularly if you also take blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin. Some evidence suggests that giving fish oil intravenously (IV) improves symptoms.
• Folic acid. If you take methotrexate, you may need to take a folic acid supplement. Ask your doctor, though -- DO NOT just take a supplement on your own.
• Shark cartilage. Early evidence suggests that shark cartilage may relieve symptoms in people with plaque psoriasis. DO NOT take shark cartilage if you have diabetes. If you take calcium supplements, talk to your doctor before taking shark cartilage. Shark cartilage can interact with some medications. It can also be expensive, and many people experience similar results with less expensive therapies.
• Gluten-free diet. Studies suggest that psoriasis and celiac disease share common pathways. A gluten-free diet may help improve psoriatic skin disease.

DO NOT take vitamin A and D supplements. Both are used in prescription medications in high doses. Also, taking a supplement with your prescription medication could be dangerous if you get too much of these vitamins.

Herbs

Herbs are a way to strengthen and tone the body's systems. As with any therapy, you should work with your health care provider to diagnose your problem before starting treatment. You may use herbs as dried extracts (capsules, powders, or teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, make teas with 1 tsp. herb per cup of hot water. Steep covered 5 to 10 minutes for leaf or flowers, and 10 to 20 minutes for roots. Drink 2 to 4 cups per day. You may use tinctures alone or in combination as noted.

• Oregon grape (Mahonia aquifolium), 10% in a cream. Some evidence suggests that using a specific cream (Relieva) made with Oregon grape may slightly reduce symptoms of psoriasis. It is not clear whether this cream works as well as conventional medications, although one study found it worked as well as calcipotriene (Dovonex) for some people.
• Avocado and vitamin B12 cream. Early research suggests that a proprietary cream containing avocado oil and vitamin B12 may reduce the symptoms of psoriasis. More research is needed.
• Aloe (Aloe vera), 0.5% in a cream. Several studies show that using an aloe cream improves psoriatic plaques better than placebo.
• Forskolin (Coleus forskohlii). Has been historically used for psoriasis, although there is no scientific evidence to show it works. People with heart disease should not use Forskolin unless directed to do so by their physicians. People who take nitrates or nitroglycerin, or drugs called calcium channel blockers, such as diltiazem (Cardizem, Dilacor, Tiazac), nifedipine (Procardia), and verapamil (Calan, Verelan), should not take forskolin. Forskolin may increase the risk of bleeding, especially if you already take blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin.
• Oregano oil. Some people say that oregano oil helps their psoriasis symptoms, although no scientific studies have been done. Oregano can potentially promote miscarriage in pregnant women, and can interact with lithium, a medication taken to treat bipolar disorder.

Homeopathy

Few studies have examined the effectiveness of specific homeopathic remedies. However, professional homeopaths may recommend one or more of the following treatments for psoriasis based on their knowledge and clinical experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type, includes your physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for a particular individual.

• Apis mellifica. For skin rashes that feel hot and dry and are sensitive to touch. Symptoms improve with cool baths and worsen with heat. This remedy is most appropriate for individuals who often feel sad, disappointed, or even depressed. They tend to cry easily but may also be irritable and envious by nature.
• Calendula. Used topically, particularly if the affected area becomes inflamed. This remedy will soothe but not cure the skin condition.
• Rhus toxicodendron. Used for psoriatic arthritis and for skin disorders accompanied by intense itching that worsen at night and improve with the application of heat. This remedy is most appropriate for individuals who are generally restless and unable to get comfortable at night.
• Sulphur. For skin disorders that are accompanied by intense itching. This remedy is most appropriate for individuals who are thirsty, irritable when not feeling well, uninspired and messy under ordinary circumstances, and who describe a sensation of internal heat and burning. Symptoms tend to improve with open, cold air and worsen with warmth.

Chiropractic

A few case studies have reported that spinal manipulation may reduce skin lesions in some people. Researchers do not know whether chiropractic care is helpful for all people with psoriasis.

Acupuncture

Acupuncture may help some people with psoriasis, although the evidence is not clear.

See your doctor regularly until your psoriasis is under control.

Many of the conventional medications used for psoriasis can cause birth defects. Pregnant women, and those planning to become pregnant, should not take these medications. Tell your doctor if you plan to become pregnant so you can talk about changing your medication.

Psoriasis may increase the risk of diabetes and heart attack. Studies also show that people with psoriasis are at increased risk of developing psychiatric disorders, including depression and anxiety, compared to unaffected individuals. Check with your doctor for follow up.

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