Imiquimod: A treatment for some skin cancers, genital warts
Imiquimod (ih-mih-kwih-mod) is a prescription medicine that you use at home. It comes in a cream that you apply to your skin. Your dermatologist may prescribe imiquimod to treat:
- Actinic keratosis (AK).
- Basal cell carcinoma (the earliest form of this skin cancer).
- Genital warts.
Sometimes, a dermatologist will prescribe imiquimod to treat another skin condition.
For your dermatologist to prescribe imiquimod, you must:
- Be willing to apply the medicine as instructed.
- Return for follow-up appointments.
- Have a normally functioning immune system.
Will imiquimod cure me?
Many patients see actinic keratoses (AKs) and the earliest form of basal cell cancer clear. This medicine also destroys genital warts.
Some patients, however, continue to get new AKs, skin cancers, or genital warts. Imiquimod can destroy a tumor or wart — but not its cause.
What causes AKs and skin cancers: AKs and skin cancers develop in people who use tanning beds, sunlamps, or do not protect their skin from the sun. Tanning beds, sunlamps, and the sun damage our skin. When the damage is severe, new AKs and skin cancers can form. Protecting your skin from the sun and not using tanning beds or sunlamps helps to reduce the chance of new getting AKs and skin cancers.
How do I use imiquimod?
You apply the cream to the AKs, skin cancer, or warts. Most patients apply imiquimod before bedtime. You must leave imiquimod on your skin for several hours and then wash it off.
Be sure to follow the directions carefully. Using more than directed can cause unwanted skin reactions. If you use the medicine less often than prescribed, it may not work.
How long will I have to use imiquimod?
This varies from patient to patient. Your dermatologist will tell you how long you will need to use the cream and how often to apply it. The following table shows the typical treatment plan for each of the skin diseases that the U.S. Food and Drug Administration (FDA) approved imiquimod to treat.
How to use imiquimod
|Skin disease||How often apply||How long keep it on your skin||How long use|
|AKs||2 days a week||8 hours||16 weeks|
|Early basal cell carcinoma||5 days a week||8 hours||6 weeks, continuing to use even if tumor disappears|
|Genital warts||3 days a week||6 to 10 hours||Maximum of 16 weeks|
How does imiquimod work?
Imiquimod stimulates the patient’s immune system. This helps the patient’s body to destroy the genital warts, AKs, or cancer cells.
When using imiquimod to treat AKs or skin cancer, your skin should react. You may have redness, swelling, burning, itching, and tenderness. As the skin starts to heal, you will see scabs and flaking. These reactions indicate that the medicine is working. When a patient does not have a reaction, imiquimod tends to be ineffective.
Do I need to take any precautions while using imiquimod?
When using this medicine, you should:
- Keep all appointments with your dermatologist. These follow-up visits allow your dermatologist to determine if the medicine is working for you. You should never use your own judgment to determine this. Your dermatologist considers many factors, not only whether your skin is clearing. If the medicine does not work, you may need to use a different treatment to prevent the disease from progressing.
- Protect your skin from the sun. This helps reduce your risk of developing new AKs and skin cancers. To do this, you should seek shade when outdoors; wear long sleeves, pants, a wide-brimmed hat, and sunglasses; and use a sunscreen. Be sure to use sunscreen that is broad-spectrum, SPF30+, and water-resistant.
- Avoid sexual activity while the medicine is on your skin. Even if you use a condom or other type of protection, this may not prevent the imiquimod from spreading to your partner.
What are possible side effects?
It is normal to have a skin reaction. This tells you that the medicine is working. You may experience redness, swelling, and itching. If the intensity becomes too much, you should contact your dermatologist. Your dermatologist can adjust the dose or frequency to make you more comfortable.
If you experience any of the following side effects, you should contact your dermatologist:
- Intense burning and itching.
- Sores that ooze.
- Flu-like symptoms.
- Upper respiratory tract infection.
- Back pain.
If you are treating AKs, you may see more AKs on your skin. This happens frequently and should not worry you.
Images used with permission of Journal of the American Academy of Dermatology J Am Acad Dermatol. 2002; 47:S240-8.
Imiquimod treats many patients safely and effectively, but it is not right for everyone. If your dermatologist mentions imiquimod as a possible treatment, be sure to tell your dermatologist if you have:
- A disease that affects your immune system, such as HIV, AIDS, rheumatoid arthritis (RA), psoriasis, or graft vs. host disease.
- Treated this skin condition in the past and what treatment you used.
You also should tell your dermatologist if you take:
- Any medicine (including ones you buy without a prescription, such as aspirin).
- Herbal supplements.
Talk with your dermatologist about concerns
If you have any concerns about using imiquimod, you should tell your dermatologist. Dermatologists have been prescribing this medicine for years. In fact, dermatologists led many of the clinical trials for imiquimod. This makes dermatologists very familiar with the medicine and knowledgeable about whom it can help.
Before talking about concerns, it may be helpful to know the advantages and disadvantages of using this medicine, which are shown below.
Imiquimod has advantages and disadvantages
Dermatologists continue to lead research studies that look at how imiquimod can help improve the lives of their patients.