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MASOPROCOL (Topical) **

** Not commercially available in the U.S. and Canada.



Masoprocol (ma-SOE-pro-kole) is applied to the skin to treat a condition called actinic keratoses, which can become cancerous if not treated.

This medicine was withdrawn from the U.S. market in June 1996.

Before Using This Medicine

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For topical masoprocol, the following should be considered:

Allergies- Tell your doctor if you have ever had any unusual or allergic reaction to masoprocol. Also tell your health care professional if you are allergic to any other substances, such as sulfites or other preservatives or dyes. Masoprocol for use on the skin contains sulfites.

Pregnancy- Tell your doctor if you are pregnant or if you intend to become pregnant. Although masoprocol applied to the skin has not been shown to cause problems in humans, some of it is absorbed through the skin. Be sure that you have discussed this with your doctor before using this medicine.

Breast-feeding- Although masoprocol applied to the skin has not been shown to cause problems in nursing babies, some of it is absorbed through the skin.

Children- There is no specific information comparing use of masoprocol on the skin in children with use in other age groups.

Older adults- Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. Although there is no specific information comparing use of masoprocol on the skin in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than it does in younger adults.

Proper Use of This Medicine

Keep using this medicine for the full time of treatment. However, do not use this medicine more often or for a longer time than your doctor ordered . Apply enough medicine each time to cover the entire affected area with a thin layer.

After washing the area with mild soap and water and drying carefully, use your fingertips to apply the medicine in a thin layer to your skin and rub it in gently.

Make sure you wash your hands immediately after applying the cream , to prevent any of the medicine from accidentally getting in your eyes or mouth.

Masoprocol commonly causes redness, soreness, swelling, itching, dryness, and flaking of affected skin. This effect will go away about 2 weeks after you stop using the medicine. However, do not stop using this medicine without first checking with your doctor. If this reaction occurs, check with your doctor.

Dosing- The dose of masoprocol will be different for different patients. Follow your doctor's orders or the directions on the label . The following information includes only the average dose of masoprocol. If your dose is different, do not change it unless your doctor tells you to do so.

  • Adults-Use the 10% cream on the affected areas of skin two times a day.
  • Children-Use and dose must be determined by your doctor.

Missed dose- If you miss a dose of this medicine, apply it as soon as possible. However, if more than a few hours have passed, skip the missed dose and go back to your regular dosing schedule. If you miss more than one dose, check with your doctor.

Storage- To store this medicine:

  • Keep out of the reach of children.
  • Store away from heat and direct light.
  • Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
  • Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Precautions While Using This Medicine

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.

Apply this medicine very carefully when using it on your face. Avoid getting any in your eyes, nose, or mouth .

This preparation contains sulfites as a preservative. Sulfites may cause an allergic reaction in some people. Signs of an allergic reaction to sulfites include bluish discoloration of skin, severe dizziness or feeling faint, or wheezing or trouble in breathing. If any of these signs occur, check with your doctor immediately .

Side Effects of This Medicine

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if the following side effect occurs:

Less common

Blistering or oozing where medicine is applied

Signs and symptoms of allergic reaction to sulfites

Bluish discoloration of skin; dizziness (severe) or feeling faint; wheezing or trouble in breathing

Check with your doctor as soon as possible if the following side effects occur:

More common

Redness, soreness, swelling, itching, dryness, and flaking of skin where medicine is applied

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue, worsen, or are bothersome:

More common

Burning feeling where medicine is applied

Less common

Leathery feeling to skin; skin roughness; wrinkles

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Developed: 07/31/1995
Revised: 10/13/2000

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.