1. Moderate to Severe Psoriasis Slideshow
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Medical Author:

Gary W. Cole, MD, FAAD

Gary W. Cole, MD, FAAD

Dr. Cole is board certified in dermatology. He obtained his BA degree in bacteriology, his MA degree in microbiology, and his MD at the University of California, Los Angeles. He trained in dermatology at the University of Oregon, where he completed his residency.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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Anthralin (Dithranol, Anthra-Derm, Drithocreme) is a synthetic form of a tree bark extract that is considered to be one of the most effective antipsoriatic agents available. However, it can cause skin irritation and staining of clothing and skin.

• How tree bark extract works: This medicine slows the production of excess skin cells.
• Who should not use these medications: Individuals with anthralin allergy or recent or excessively swollen patches should not use anthralin.
• Use: Apply a small amount of the cream, ointment, or paste to the patches on the skin. On the scalp, remove scales and rub into affected areas. Avoid the forehead, eyes, and any skin that does not have patches. Do not apply excessive quantities. Short applications of a high concentration for only 20 minutes, followed by washing with soap and water can be used to minimize skin irritation.
• Drug or food interactions: Anthralin is combined with salicylic acid in preparations used for psoriasis treatment.
• Adverse effects: Anthralin stains clothing or linens purple or brown. Use with caution if the individual has kidney disease. Care must be taken to apply this medication only to psoriasis patches and not to surrounding normal skin. Anthralin may cause skin discoloration (increased pigment) and may burn or irritate skin. Do not use on the face, neck, skin folds (back of knees or elbows), or genitals. Avoid contact with the eyes. Do not use on excessively irritated patches. This medication should only be used if the patient can comply with instructions for use.

Tazarotene (Tazorac) is a topical retinoid that is available as a gel or cream. This medicine is sometimes combined with corticosteroids to decrease skin irritation when used alone and to increase effectiveness. Tazarotene is particularly useful for psoriasis of the scalp.

• How topical retinoids work: They reduce the size of psoriasis patches and the redness of the skin.
• Who should not use these medications: Individuals with the following conditions should not use topical retinoids:
• Allergy to retinoids
• Pregnancy (Note: A pregnant woman should not use or take a retinoid medicine.)
• Breastfeeding
• Use: Apply a thin film to the affected skin every day or as instructed. Dry skin before using this medicine. Irritation may occur when applied to damp skin. Wash hands after application. Do not cover with a bandage.
• Drug or food interactions: Cosmetics or soap products that dry or irritate the skin may worsen the irritation and dry skin when used with a topical retinoid.
• Adverse effects: Do not use this medicine on the face, around the eyes, or inside the nose or mouth. Do not use on open wounds or sunburned skin. This medicine may cause burning or stinging. Sensitivity to the sun may occur. If skin irritation or pain increase, contact a doctor.

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