DRITHOCREME HP

Anthralin (also known as dithranol) is a synthetic topical antipsoriatic agent and a derivative of anthracene. It is used for quiescent or chronic psoriasis. Anthralin also may be used for alopecia, although it is not FDA-approved for this indication. Do not apply to face, genitalia, eyes, open sores, or mucous membranes because painful irritation can occur. Protective dressings to shield unaffected skin are recommended. This agent can stain fabric, skin, or hair with a yellow-brown color; stains can be permanent. Anthralin was initially marketed for use before 1962, which is when Congress passed the amended Federal Food, Drug, and Cosmetic Act requiring that the FDA establish both safety and efficacy for all subsequently approved drugs. Anthralin products are unapproved marketed drugs that have not been formally evaluated by the FDA.

General Administration Information
For storage information, see the specific product information within the How Supplied section.

Route-Specific Administration

Topical Administration
-For topical dermatological use only. Avoid contact with the eyes or mucous membranes.
-Due to the propensity of anthralin to stain and cause skin irritation, always wash hands thoroughly after use.
-Apply with care to avoid staining clothing, bed linens, or other objects. Anthralin cream may permanently stain fabrics, and may cause discoloration of tubs/showers. Rinse tub/shower with lukewarm water and wash with a suitable cleanser if medication comes in contact with surface.
-Avoid application to unaffected skin. In order to minimize contact with surrounding skin, it may be advisable to apply zinc oxide or petroleum jelly to edges of the affected area prior to application.
Cream/Ointment/Lotion Formulations
Anthralin cream:
-Anthralin is a known skin irritant. When initiating therapy, use a short contact time (5-15 minutes) for at least 1 week. Contact time may be increased stepwise to 30 minutes before removing the cream by washing or showering depending on the patient's response to treatment.
-Use caution when applying to the face or intertriginous skin areas as excessive irritation may develop.
-For the skin: Apply sparingly to affected areas and rub in gently. Rinse skin thoroughly at the end of the treatment period with cool to lukewarm water before washing with soap.
-For the scalp: Cleanse hair with shampoo and rinse. While the hair is still damp, apply sparingly and rub well into the affected areas. Remove any residue which may be deposited behind the ears. At the end of each treatment period, rinse hair and scalp thoroughly with cool to lukewarm water and then shampoo the hair and scalp to remove any surplus.
Anthralin shampoo:
-Apply to wet scalp and lather. Leave on for 3-5 minutes and rinse thoroughly. Avoid contact with eyes.
-No additional shampoo is necessary; however, a non-medicated shampoo or conditioner may be applied after anthralin shampoo, if desired.

Some skin irritation or a feeling of warmth is a common side effect during application of anthralin. High strengths or long application times may result in transient burning-sensations and worse skin irritation. If excessive soreness occurs or if the lesions spread, it may be necessary to reduce frequency of application or discontinue use. Exposed skin areas may be prone to photosensitivity. Anthralin readily stains fabric, hair and other objects; stains are a yellow-brown color and in can be permanent on fabrics and clothing. Temporary skin discoloration of the area surrounding the treated lesions is possible. Temporary hair discoloration and nail discoloration can be minimized by careful application, use of protective dressings to shield unaffected areas, and the use of gloves during application.

The use of anthralin is contraindicated in patients with acute or actively inflamed psoriatic eruptions and those with a history of hypersensitivity reactions to anthralin or any components used in the preparation of the commercial product.

Anthralin may stain fair hair, clothing, or other objects. To prevent the possibility of staining clothing or bed linen, it may be advisable to use protective dressings with anthralin. To prevent discoloration of tub/shower, always rinse the tub/shower with lukewarm water immediately after washing and then use a suitable cleanser on the surface of the tub or shower. Contact with fabrics, plastics and other materials may cause staining and should be avoided. Always wash hands thoroughly after use.

Application of anthralin to human mucous membranes is not recommended. Use caution when applying to the face or intertriginous skin areas; excessive irritation may develop. This medication is not for ophthalmic administration; care should be taken to avoid ocular exposure.

The safety and efficacy of anthralin cream have not been formally established in neonates, infants, children, and adolescents. The safety and efficacy of anthralin shampoo have not been established in neonates, infants, and children < 12 years. Anthralin has been used for the therapy of alopecia areata in children and adolescents, but this use is not FDA-approved.

According to the FDA-approved labeling, it is not known if anthralin can cause fetal harm when administered to a pregnant woman. Due to the lack of human data, anthralin should be used during pregnancy only if clearly needed.

According to the manufacturer, a decision should be made whether to discontinue nursing or to discontinue anthralin, taking into account the importance of the drug to the mother. It is not known if anthralin is excreted in human milk. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.

Areas treated with anthralin may rarely exhibit photosensitivity. Patients may need to limit sunlight (UV) exposure of treated areas and take appropriate precautions against unwanted UV exposure.

For the treatment of stable plaque psoriasis:
-for psoriatic lesions on the skin:
Topical dosage:
Adults: Apply sparingly to psoriatic lesions once daily and leave on for up to 30 minutes; rinse skin thoroughly with cool to lukewarm water then wash with soap. Initially, a contact time of 5-15 minutes is recommended for at least 1 week, titrated up to a duration of 30 minutes according to response.
Neonates, Infants, Children, and Adolescents: Safety and efficacy have not been established.
-for the treatment of scalp psoriasis:
Topical dosage (cream):
Adults: After cleansing hair, apply once daily to psoriatic scalp lesions while hair is still damp; leave on for up to 30 minutes then rinse hair and scalp thoroughly with cool to lukewarm water and then shampoo the hair and scalp to remove any surplus cream. Initially, a contact time of 5-15 minutes is recommended for at least 1 week, titrated up to a duration of 30 minutes according to response.
Topical dosage (shampoo):
Adults, Adolescents, and Children >= 12 years: Apply topically 3-4 times per week to wet scalp. Lather and leave on for 3-5 minutes then rinse thoroughly. Instruct patients to use anthralin shampoo for the minimum time period necessary to achieve the desired results; consult a physician if no improvement after 4 weeks.

For the treatment of alopecia areata*:
Topical dosage:
Adults, Adolescents, and Children: Apply anthralin topically to affected areas once daily; initially leave on for 20-30 minutes and titrate as tolerated up to 60 minutes then shampoo off. Some patients tolerate overnight application. Some patients may fail to achieve cosmetically significant results. Various strengths ranging from 0.1% up to 2% have been described in the medical literature; some dermatologic formulations described in the literature may require extemporaneous compounding.

Maximum Dosage Limits:
-Adults
1 application/day to each affected area for cream; 1 application/day up to 4 days/week for shampoo.
-Geriatric
1 application/day to each affected area for cream; 1 application/day up to 4 days/week for shampoo.
-Adolescents
1 application/day to each affected area for cream; 1 application/day up to 4 days/week for shampoo.
-Children
>= 12 years: Cream: 1 application/day up to 4 days/week for shampoo.
< 12 years: Cream: Safety and efficacy have not been established.
-Infants
Safety and efficacy have not been established.
-Neonates
Safety and efficacy have not been established.

Patients with Hepatic Impairment Dosing
No dosage adjustment needed.

Patients with Renal Impairment Dosing
No dosage adjustment needed.

*non-FDA-approved indication

There are no drug interactions associated with Anthralin products.

The exact mechanism of anthralin is unknown. However, anti-proliferative and anti-inflammatory effects of anthralin have been demonstrated on psoriatic and normal skin. The anti-proliferative effects of anthralin appear to result from both an inhibition of DNA synthesis as well as from strong reducing properties. The effectiveness of anthralin as an anti-psoriatic agent has partly been attributed to its abilities to induce lipid peroxidation and to reduce levels of endothelial adhesion molecules, which are markedly elevated in psoriatic patients.

Anthralin is administered topically. Although the extent of systemic absorption after topical application has not been determined, no traces of anthraquinone metabolites were detected in the urine of treated subjects in a limited clinical study of anthralin cream. Anthralin does not inhibit hepatic microsomal enzyme activity.