Zithranol-RR is a prescription medication approved by the Food and Drug Administration (FDA). Zithranol-RR became available in 2009 for the treatment of plaque psoriasis affecting the skin or scalp. Zithranol-RR is also known by its drug name, Dithranol. Anthralin is another drug name for Zithranol-RR; Dithranol and Anthralin may be used interchangeably.
Zithranol-RR should be used with caution in people with a history of kidney disease. Zithranol-RR may not be appropriate for use by pregnant women or women who are breastfeeding.
Anthralin, the active ingredient in Zithranol-RR, is a synthetic form of a compound found in the bark of a tree indigenous to South America. It is believed that Zithranol-RR works in cases of psoriasis by reducing inflammation and slowing cell growth.
How do I take it?
Zithranol-RR is applied to the skin once daily for a limited period, usually 5 to 30 minutes. Your doctor will provide directions on the appropriate amount of time to leave Zithranol-RR on your skin. For psoriasis on the scalp, your doctor may tell you to apply Zithranol-RR every other day.
Apply Zithranol-RR only to skin affected by psoriasis. You can protect surrounding healthy skin from irritation with a layer of petroleum jelly before applying Zithranol-RR. Wash your skin with soap before applying Zithranol-RR. If applying Zithranol-RR to the scalp, first wash your hair with shampoo to remove any loose scales, and then apply Zithranol-RR while the hair is still damp. After leaving Zithranol-RR on for the amount of time indicated by your doctor, first rinse it off with cool or lukewarm water, and then wash again with soap or shampoo and hot water.
Zithranol-RR should be used with caution on the face, genitals, between fingers and toes, or on skin folds. Wear disposable gloves while applying Zithranol-RR to avoid discoloration of the fingernails. If you do not wear disposable gloves, after applying Zithranol-RR first rinse your hands with lukewarm water, then wash with hot water and soap.
Do not apply Zithranol-RR to irritated or acutely inflamed skin. Avoid getting Zithranol-RR onto mucus membranes of your eyes, nose, mouth, or genitals.
Zithranol-RR can stain skin and light-colored hair and permanently stain fabric. Take care to protect clothes and furnishings when using Zithranol-RR.
Always follow your doctor’s instructions exactly when using Zithranol-RR.
In clinical trials, Anthralin (Zithranol-RR) provided significant improvement in cases of psoriasis in comparison with the placebo. Anthralin is considered to be a practical and effective treatment for psoriasis.
Side effects of Zithranol-RR may include irritation and redness. These effects may fade as your body becomes accustomed to the medication.
Contact your doctor if your psoriasis worsens or spreads while using Zithranol-RR.
Many drugs can cause allergic reactions that, in the most serious cases, can result in death. Seek immediate medical help if you experience signs of a severe allergic reaction such as difficulty breathing or swelling in the face, throat, eyes, lips, or tongue.