Medical Editor: John P. Cunha, DO, FACOEP Last updated on RxList: 9/25/2023

Drug Summary

What Is Dritho-Scalp?

Dritho-Scalp (anthralin) Topical Cream is an antipsoriatic medication used to treat long-term psoriasis of the scalp. Dritho-Scalp may be available in generic form.

What Are Side Effects of Dritho-Scalp?

Common side effects of Dritho-Scalp include:

  • temporary redness or irritation of the treated scalp
  • temporary discoloration of hair and fingernails, or
  • staining of skin or hair.

Dritho-Scalp may permanently stain fabrics.

Seek medical care or call 911 at once if you have the following serious side effects:

  • Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
  • Serious heart symptoms such as fast, irregular, or pounding heartbeats; fluttering in your chest; shortness of breath; and sudden dizziness, lightheadedness, or passing out;
  • Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors.

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

Dosage for Dritho-Scalp

Apply a dose of Dritho-Scalp once a day or as directed by a physician.

What Drugs, Substances, or Supplements Interact with Dritho-Scalp?

Dritho-Scalp may interact with other drugs. Tell your doctor all medications and supplements you use.

Dritho-Scalp During Pregnancy or Breastfeeding

During pregnancy, Dritho-Scalp should be used only if prescribed. It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

Additional Information

Our Dritho-Scalp (anthralin) Topical Cream Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

Drug Description

Important Information about Dritho-Scalp®

Warning - Dritho-Scalp® can cause severe irritation. Be careful to keep off skin not affected by psoriasis. Rinse immediately after 5 minutes or the amount of time your doctor prescribed. If irritation occurs, discontinue use and call your doctor. Keep away from eyes.

Caution - Dritho-Scalp® can permanently stain clothing and bathroom fixtures. Dritho-Scalp will also stain skin, but skin staining is temporary. Use only old clothing and old towels and linens when using Dritho-Scalp. Any clothing or linens that come in contact with Dritho-Scalp may become permanently stained. Rinse all bathroom fixtures immediately and thoroughly.


Dritho-Scalp® is a pale yellow topical cream containing 0.5% anthralin USP in a base of white petrolatum, mineral oil, sodium lauryl sulfate, cetostearyl alcohol, ascorbic acid, salicylic acid, methylparaben and purified water. The chemical name of anthralin is l,8-dihydroxy-9- anthrone. The structural formula is:

Dritho-Scalp (anthralin) Structural Formula Illustration

Indications & Dosage


An aid in the topical treatment of quiescent or chronic psoriasis of the scalp. Treatment should be continued until the skin is entirely clear, i.e., when there is nothing to feel with the fingers and the texture is normal.


Generally, it is recommended that Dritho-Scalp be applied once a day or as directed by a physician. Anthralin is known to be a potential skin irritant. The irritant potential of anthralin is directly related to each patient's individual tolerance. Therefore, where the response to anthralin treatment has not previously been established, always commence treatment using a short contact time of 5 to 10 minutes for at least one week using Dritho-Scalp. Contact time can be increased stepwise to twenty to thirty minutes, or as directed by a physician, before removing the cream by thoroughly washing or showering. Apply as directed by a physician. The optimal period of contact will vary according to the patient's response to treatment.

To open the tube, unscrew the cap and invert to pierce the membrane. Comb the hair to remove scalar debris and, after suitably parting, apply Dritho-Scalp only to the lesions and rub in well, taking care to prevent the cream spreading onto the forehead.

Keep Dritho-Scalp well away from the eyes.

Avoid application of the cream to uninvolved scalp margins. Remove any unintended residue which may be deposited behind the ears. At the end of each period of contact, wash the hair and scalp to remove any surplus cream (which may have become red/brown in color).

Always wash hands thoroughly after use.

Store at controlled room temperature, 15-30C (59-86F).


50 g tube

Manufacturer details: n/a

Side Effects & Drug Interactions


Very few instances of contact allergic reactions to anthralin have been reported. However, transient primary irritation of uninvolved skin surrounding the treated lesions is more frequently seen and may occasionally be severe. Application of Dritho-Scalp must be restricted to the psoriatic lesions. If the initial treatment produces excessive soreness or if the lesions spread, reduce frequency of application and, in extreme cases, discontinue use and consult physician. Some temporary discoloration of hair and fingernails may arise during the period of treatment but should be minimized by careful application. Dritho-Scalp may stain skin, hair or fabrics. Staining of fabrics may be permanent, so contact should be avoided.


No information provided.

Warnings & Precautions


Avoid contact with the eyes or mucous membranes. Dritho-Scalp should not normally be applied to intertriginous skin areas and high strengths should not be used on these sights. Remove any unintended residue which may be deposited behind the ears. Avoid applying to the folds and creases of the skin. Discontinue use if a sensitivity reaction occurs or if excessive irritation develops on uninvolved skin areas. Keep out of the reach of children.


For external use only. Dritho-Scalp may stain the hair and should be applied sparingly and carefully to psoriatic lesions only. Contact with fabrics, plastics and other materials may cause staining and should be avoided. To prevent the possibility of discoloration, always rinse the bath/shower with hot water immediately after washing/showering and then use a suitable cleanser to remove any deposit on the surface of the bath or shower. Always wash hands thoroughly after use, 15-30° C (59-86° F). Long-term studies in animals have not been performed to evaluate the carcinogenic potential of the drug. Although anthralin has been found to have tumor-promoting properties on mouse skin, there have been no reports to suggest carcinogenic effects in humans after many years of clinical use. As long-term use of topical corticosteroids may destabilize psoriasis, and withdrawal may also give rise to a 'rebound' phenomenon, an interval of at least one week should be allowed between the discontinuance of such steroids and the commencement of Dritho-Scalp therapy. Petrolatum or a suitably bland emollient may usefully be applied during the intervening period.


Pregnancy Category C. Animal reproduction studies have not been conducted with Dritho-Scalp. It is also not known whether Dritho-Scalp can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Dritho-Scalp should be given to a pregnant woman only if clearly needed.

Nursing Mothers

It is not known whether this drug is excreted in human milk. Because many drugs are excreted in milk and because of the potential for tumorigenicity shown for anthralin in animal studies, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

Safety and effectiveness in pediatric patients have not been established.

Overdose & Contraindications


No information provided.


In patients with acute psoriatic eruptions or a history of hypersensitivity to any of the ingredients.

Clinical Pharmacology


Although the precise mechanism of anthralin's anti-psoriatic action is not fully understood, in vitro evidence suggests that its antimitotic effect results from inhibition of DNA synthesis. Additionally, the chemically reducing properties of anthralin may upset oxidative metabolic processes, providing a further slowing down of epidermal mitosis. Absorption in man has not been finally determined, but in a limited clinical study of anthralin cream, no traces of anthraquinone metabolites were detected in the urine of subjects treated; however, caution is advised in patients with renal disease.

Medication Guide


Easy Dritho-Scalp® Application Instructions

  1. Wet your scalp thoroughly.
  2. Wet your scalp thoroughly - illustration

  3. Part off your hair one inch at a time to examine and treat each plaque.
  4. Wearing disposable gloves, apply a "pea size" drop of Dritho-Scalp® directly to all plaques by rubbing in thoroughly but gently. Avoid ears, eyes and neck, and be careful not to smear on unaffected skin. Tip: Petroleum jelly can be applied to ear folds and neck to minimize contact and avoid irritation.
  5. Apply a "pea size" drop of Dritho-Scalp - illustration

  6. Cover scalp with shower cap to prevent staining and smearing. Line the edges of the cap with cotton coil or folded tissues.
  7. Cover scalp with shower cap - illustration

  8. Do not leave Dritho-Scalp® on any longer than directed by your dermatologist. Remove immediately when time is up.
  9. Remove immediately when time is up  - illustration

  10. Shampoo out thoroughly but gently. Lean head back when rinsing to avoid Dritho-Scalp® contact with the face and eyes. If it gets into your eyes or on your face, rinse thoroughly and call your dermatologist.
  11. Immediately clean the shower or bathroom fixture, rinsing thoroughly. Dishwashing detergent may help to remove residue.
  12. Dry off with an old towel as staining of fabrics is permanent.
  13. Dry off with an old towel - illustration

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