Psoriasis is a common skin disorder marked by raised, inflamed lesions that join together to form plaques with distinct borders on the skin and may be covered with flaky scales. It can also exist as small, scaly droplet-like lesions (guttate psoriasis). A wide range of medications may be used to treat psoriasis. The type of psoriasis medication prescribed depends on several factors, including:

• Type of psoriasis present
  
  
• Location of lesions on the body
  
  
• Severity of psoriasis present
  
  
• Patient’s overall health, age and medical history
  
  
• Patient’s tolerance of specific medications, procedures or therapies
  
  
• Patient and physician’s opinion or preference

Topical medications are usually the first treatment choice for psoriasis. Topical treatments, such as creams and ointments, are placed on the skin surface, as opposed to medications that are taken orally or injected (systemic). They may be used to slow or normalize the growth rate of skin cells and reduce inflammation associated with mild to moderate psoriasis. They may be used alone, in combination with each other, oral or injected medications, or with controlled exposure to ultraviolet light (phototherapy). Generally, any scales present need to be removed before application because they block medication penetration. Combining topical medications that include urea, salicylic acid or vitamin D often accomplishes this.

Some psoriasis medications are available in both topical and oral forms. Oral medications may be used for severe, life-threatening cases of psoriasis that do not respond to other forms of treatment. They may be used alone or in combination with topical, other oral or injected medications. These are more dangerous than topical treatments as some may cause life-threatening complications. Therefore their benefits of use must be weighed against the possible side effects. Psoriasis medications may also sometimes be injected to treat severe localized lesions.

Numerous medications are used to treat psoriasis. They may be used in combination with each other or with phototherapy (controlled exposure to ultraviolet light) to increase their effectiveness or reduce the likelihood of side effects.

Medications commonly used to treat psoriasis include:

• Emollients. Topical medications that are widely available without a prescription. They help restore moisture and flexibility to skin affected by psoriasis. They also help reduce scaling, itching (pruritus) and inflammation. When psoriasis is very mild, emollients may be the only treatment needed. Mild moisturizers without heavy perfumes are typically better for treating psoriatic skin. Emollients are often used for mild psoriasis or in combination with other treatments for moderate to severe psoriasis.
  
  
• Salicylic acid. A topical compound that is widely used to treat psoriasis. It is frequently used in combination with other topical medications because it removes surface scales and enhances the penetration of other medications into the affected skin. Salicylic acid is available over-the-counter and by prescription.
  
  
• Coal tar. Among the oldest treatments for psoriasis and may be used for mild to moderate psoriasis that is not pustular. Modern preparations are much less messy and smelly than those of the past. Coal tar preparations are available both with and without a prescription. Although it is not known precisely how they work, these preparations seem to reduce the accelerated skin cell cycle characteristic of psoriasis. Coal tar also has anti-inflammatory properties and eases pruritus. It is available in many forms (e.g., bath oils, ointments, lotions, cleaning bars, shampoos) and may be used in conjunction with phototherapy.

        Coal tar preparations for psoriasis include:

• Topical corticosteroids. The most commonly used medications for localized areas of mild to moderate psoriasis. They are available in a wide range of forms and strengths and may be used to reduce the rapid growth of skin cells as well as inflammation and pruritus. They can be used on sensitive areas (e.g., skin folds, genitalia) for short periods of time. Corticosteroids can also be injected directly into an isolated lesion. Corticosteroids are typically not used for long-term psoriasis treatment, because prolonged use may actually worsen psoriasis. Topical corticosteroids are available over-the-counter and by prescription.
  
  Topical corticosteroids used in the treatment of psoriasis include:

Generic Name	Brand Name(s)
betamethasone	Alphatrex Betatrex Beta-Val Celestone Diprosone Dirolene Luxiq Maxivate
triamcinolone	Aristocort Flutex Kenalog Triacet
clobetasol	Temovate
fluocinolone	Derma-Smoothe/FS FS Shampoo Fluonid Flurosyn Synalar Synemol

• Anthralin. A topical prescription medication used to treat psoriasis by normalizing the growth rate of skin cells. It is also helpful in removing scales and smoothing the skin. In can be used both on the body and the scalp and may be used in phototherapy. However, anthralin may stain skin, hair and fabrics. A rather potent medication, it is generally used on thicker, harder-to-treat lesions, such as moderate to severe plaque or guttate psoriasis or mild lesions that are resistant to other treatments. Brand names for anthralin include Anthra-Derm, Drithocreme, Dritho-Scalp, Lasan and Micanol.
  
  
• Vitamin D analogs. Topical prescription medications derived from vitamin D. These medications may be used on sensitive areas (e.g., face, body folds) and do not typically thin the skin like corticosteroids may. They may also be used to treat psoriasis on the scalp and nails. Vitamin D analogs work by slowing down the rapid growth of skin cells. They are used to reduce lesions, remove scales and improve redness. They are odorless and do not stain. They may be used alone or in combination for mild to moderate plaque psoriasis or in combination with more potent treatments for severe psoriasis. They are often combined with corticosteroids and may produce results within two weeks of beginning therapy.
  
  Vitamin D analogs used to treat psoriasis include:

Generic Name	Brand Name(s)
calcipotriene (topical)	Dovonex
calcitriol (topical)	Calcijex Rocaltrol

• Retinoids. Prescription medications derived from vitamin A. Retinoids work by reducing rapid skin cell growth. Topical retinoids are odorless and colorless and may be used for mild to moderate plaque or nail psoriasis. They cause no long-term skin damage and can be used on sensitive areas (e.g., face, hairline, scalp). They may produce results in as little as two weeks, but optimal clearing may take up to 12 weeks. Oral retinoids may be used in severe cases of psoriasis (including erythrodermic and pustular psoriasis) that do not respond to other forms of treatment. They can be very effective, but may cause serious side effects.
  
  Retinoids used to treat psoriasis include:

Generic Name	Brand Name(s)
tazarotene (topical)	Tazorac
acitretin (oral)	Soriatane
isotretinoin (oral)	Accutane

Since it has been discovered that psoriasis is an autoimmune disease, prescription immunosuppressant medications have been used to treat moderate to severe forms of the disease. Among the most commonly used of these is the disease modifying antirheumatic drug (DMARD) methotrexate, which is used in the treatment of severe psoriasis that does not respond to other treatments. Available orally or by injection, this medication reduces rapid skin cell growth and typically produces results in four to six weeks. However, it may cause serious side effects and tests must be performed prior to use to check liver and kidney function.

The oral immunosuppressant cyclosporine may be used in low doses to treat severe psoriasis. Short term use of this drug is generally very safe and effective. However, it is not recommended to be taken for more than a year. Improvements may be seen in some patients after two weeks, but it usually takes 12 to 16 weeks to control the disease.

Many immunosuppressant medications are made from human or animal proteins. These biological agents are typically administered by injection and may produce results after about four weeks.

Certain topical immunosuppressants may be well-tolerated in the treatment of psoriasis on the face and in body folds. However, there may be a link between these medications and certain cancers (e.g., lymphoma, skin cancer). This matter is currently under investigation.

Immunosuppressants that may be used to treat psoriasis include:

Psoralens are topical and oral prescription medications that are only effective when used along with phototherapy, called PUVA. They are useful in treating mild to moderate psoriasis because they reduce the rapid growth of skin cells.

Psoralens used in psoriasis phototherapy include:

Side effects of psoriasis medications vary depending on the type of medication. A common side effect of topical treatments is skin irritation, including pruritus (itching), burning and erythema (redness).

Topical retinoids, coal tar, psoralens and systemic methotrexate may increase susceptibility to sunburn. It is recommended that patients use a sunscreen with a sun protection factor (SPF) of at least 15 and avoid unnecessary sun exposure. Another common side effect is skin irritation including scaling, redness, dryness, erythema, burning sensations, itching and peeling skin.

Coal tar and anthralin may stain skin, clothing and hair. It is generally recommended to wear gloves when applying anthralin and to avoid contact with non-affected skin.

Topical corticosteroids may induce atrophy (degeneration) of the epidermis (top layer of skin) and thin the skin. They may also dilate blood vessels, cause stretch marks and lead to allergic contact dermatitis (skin inflammation caused by an allergic reaction to a substance making contact with the skin). When used over extended periods of time, corticosteroids can actually make psoriasis worse.

Vitamin D analogs may increase calcium levels in the blood, leading to hypercalcemia. In some cases, they may cause thinning of skin, dermatitis (inflammation of the skin) and severe skin irritation.

Oral retinoids are associated with numerous side effects, including severe birth defects or miscarriages when used during pregnancy. Women of reproductive age are required to use two separate, effective forms of birth control for one month before treatment begins, during the entire course of treatment and for months to years after treatment ends depending on the type. Pregnancy tests are typically performed every month during treatment. Other side effects may include:

• Dry, fragile skin and cheilitis (inflammation and redness of the lips)
• Nosebleeds
• Headaches
• Fatigue
• Nausea and vomiting
• Abdominal pain
• Lack of appetite
• Jaundice (yellowing of the skin and/or eyes)
• Dry eyes and mucous membranes
• Muscle and joint aches
• Liver damage
• Hair loss
  
• Photosensitivity
  
• Paronychia (inflammation of the nailfold area)

Methotrexate is linked to a large number of side effects, many of them serious. The most common adverse effects are hives (smooth, raised pink or white bumps that appear on or beneath the skin), irritation, rash, nausea, vomiting, and menstrual disorders. Serious side effects include arachnoiditis (inflammation of a certain membrane in the brain), nerve damage, seizures, kidney failure, leukopenia (not enough leukocytes in the blood), thrombocytopenia (not enough platelets in the blood), and liver damage. Other side effects include:

• Fever
• Malaise (feeling of being unwell)
• Dizziness
• Headache
• Drowsiness
• Blurred vision
• Diarrhea
• Abdominal pain
• Hair loss
• Joint and muscle pain

Other immunosuppressants may also have a large number of possible side effects. Cyclosporine may cause decreased kidney function, headache and high blood pressure. Mycophenolate may lead to gastrointestinal discomfort, headache and insomnia. Azathioprine may cause nausea, vomiting and fatigue and may cause the skin to bruise easily. Injected biological agents (e.g., etanercept, alefacept, efalizumab, infliximab) may cause a sore throat, dizziness and pain, inflammation and erythema at the injection site. Injectable immunosuppressants may also trigger flu-like symptoms.

Patients should consult their physician before taking any additional prescriptions, over-the-counter medications, nutritional supplements or herbal medications. Interactions of particular concern to individuals taking psoriasis medications depend on the medication taken and may include:

• Grapefruit juice. Grapefruit juice interferes with the liver’s ability to rid the body of some substances. This could lead to a buildup of chemicals in many oral psoriasis medications (e.g., methotrexate) to toxic levels in the body. Though the buildup is less likely if the juice is ingested four or more hours before taking the medicine, patients are generally advised to refrain from drinking grapefruit juice. There is no indication that eating grapefruit (as opposed to drinking juice) presents any danger to patients.
  
  
• Retinoids. Alcohol should not be used with oral (by mouth) retinoids.
  
  
• Vitamin D analogs. Antacids, mineral oils and certain cholesterol medications may alter the absorption of some vitamin D analogs in the skin. Some antiseizure medications may reduce the activity of certain vitamin D analogs whereas corticosteroids may counteract their effects.
  
  
• Methotrexate. Must not be taken with nonsteroidal anti-inflammatory drugs (e.g., ibuprofen) as this greatly increases medication toxicity and can be fatal. Other drugs that may increase the toxicity (and therapeutic effects) of methotrexate and should be avoided include salicylates (drugs used to relieve pain and reduce fever) and sulfonamides (a class of antibiotics). Immunizations may not be effective when taking methotrexate. Oral antibiotics and folic acid may reduce the effectiveness of this medication. Alcohol should not be used with methotrexate.
  
  
• Other immunosuppressants. Immunosuppressant medications are typically not administered with other immunosuppressants because they may excessively suppress the immune system.
  
  
• Psoralens. Should not be taken with foods that contain furocoumarin (e.g., carrots, celery, figs, limes, mustard, parsley, parsnips) or medications that increase photosensitivity (e.g., coal tar products, retinoids, sulfonamides, tetracyclines, other psoralens). Some psoralens may result in abnormal liver function tests.

Symptoms of overdose can be similar to the medication’s side effects, but are usually more severe. Topical medications must not be ingested. It is recommended that patients exhibiting severe burning, itching (pruritus), swelling or excessive dryness while taking topical medications contact their physician immediately. It is also recommended that patients using salicylic acid contact their physician immediately if they exhibit any of the following:

• Confusion
• Lightheadedness
• Diarrhea
• Dizziness
• Fast or deep breathing
• Severe or continuing headache
• Hearing loss
• Nausea or vomiting

All women who are or may become pregnant should discuss the use of any psoriasis medication with their physician. Many psoriasis medications should not be used by women who are or may become pregnant. This is particularly true of oral retinoids, methotrexate and PUVA phototherapy. These are absolutely not recommended for pregnant women because of a very high risk of miscarriage or severe birth defects. The Food and Drug Administration (FDA) strictly monitors many of these medications and may require women to have two negative pregnancy tests prior to receiving a prescription.

In addition, women may be required to have monthly pregnancy tests throughout the course of isotretinoin treatment. Some of these medications (e.g., the retinoid etretinate) may remain in the system for a very long time, requiring adequate contraception for as long as two or three years following therapy. These medications are also not recommended when breastfeeding.

Topical retinoids are typically not recommended for women who are or may become pregnant. Certain topical retinoids, including tazarotene, must not be used in pregnancy.

The safety of many other psoriasis medications (e.g., anthralin, corticosteroids, vitamin D analogs) during pregnancy has not been established. Because of this, these medications are not recommended for women who are or may become pregnant. Most of these medications may also be excreted in breast milk, so they are not recommended for women who are breastfeeding.

Most psoriasis medications do not have established dosages for children. Care is advised when using salicylic acid on young children because they may be more likely to develop skin irritation. Because side effects may be worse in children, the use of psoriasis medications is typically closely monitored. Many medications (e.g., tazarotene, methoxsalen) are not recommended for use in children under the age of 12 years and others (e.g., acitretin) are only for use in adults. With long-term use, methotrexate may cause osteoporosis (loss of bone density) in children.

Preparing questions in advance can help patients to have more meaningful discussions with their physicians. Patients may wish to ask their doctors the following questions about psoriasis medications:

1. What type of psoriasis medication is best for me? Will you be prescribing medication in pill form or as a topical treatment?
   
   
2. Will I take this drug alone, in combination with other drugs or with phototherapy?
   
   
3. How and when should I take my psoriasis medication?
   
   
4. How long will I require this psoriasis medication?
   
   
5. How will this medication affect my current medical conditions other than psoriasis?
   
   
6. How will this medication interact with other medications I am currently taking?
   
   
7. What side effects may I develop?
   
   
8. What side effects should I immediately report to you?
   
   
9. How long will it take for the drug to take effect?
   
   
10. How will I know if the drug is working?
    
    
11. What will be the next step if this drug fails to relieve my symptoms?