Wart Uses, Warnings, Side Effects, Dosage

What is imiquimod, and what is it used for?

Imiquimod is a topical cream used in the treatment of certain skin disorders including external genital warts, scaly skin, and superficial basal cell carcinoma (sBCC), a type of skin cancer. Imiquimod stimulates natural immune activity to control the growth of genital warts, skin tumors, and skin disorders that cause excessive skin tissue growth leading to scaling. Imiquimod has no direct antiviral activity against the viruses that cause warts around the genitals and anus.

Imiquimod activates the body’s innate and acquired immune response by binding to toll-like receptor 7 (TLR7), a protein that plays an important role in immune response to viral infection. TLR7 activation stimulates the release of pro-inflammatory substances (cytokines), and proliferation and migration of immune cells to the affected area of the skin. The inflammatory cells cause programmed cell death (apoptosis) in tumor cells, and fight the virus in warts.

The uses of imiquimod include:

FDA-approved:

Adults

Off-label:

Adults

What are the side effects of imiquimod?

Common side effects of imiquimod include:

Application site and local skin reactions:

• Redness (erythema)
• Flaking/scaling/excoriation
• Dryness
• Scabbing and crusting
• Swelling (edema)
• Erosion and ulceration
• Weeping and discharge (exudate)
• Blisters (vesicles)
• Itching
• Burning
• Bleeding
• Pain
• Stinging
• Skin thickening (induration)
• Irritation and soreness
• Tenderness
• Skin bumps (papules)
• Infection
• Fungal infection
• Loss of pigmentation (hypopigmentation)
• Rash
• Sensitivity

Remote site skin reactions:

Systemic reactions:

Less common skin and systemic reactions:

Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:

• Serious heart symptoms include fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
• Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
• Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
• Serious eye symptoms include blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

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What are the dosages of imiquimod?

Topical Cream

• 2.5% (Zyclara)
• 3.75% (Zyclara)
• 5% (Aldara)

Adult:

Actinic Keratosis

• Indicated for topical treatment of clinically typical, nonhyperkeratotic, nonhypertrophic actinic keratoses on the face or scalp in immunocompetent adults
• Zyclara 2.5% or 3.75%: Apply daily to skin of affected area (either entire face or balding scalp) for two 2-week treatment cycles separated by 2-week no-treatment period
• Aldara 5%: Apply 2 times a week for 16 weeks to one defined treatment area (contiguous area smaller than 25 cm²); examples of dosing schedules include Monday and Thursday or Tuesday and Friday

Superficial Basal Cell Carcinoma

• Target tumor should have less than 2 cm maximum diameter and be located on trunk (excluding anogenital skin), neck, or extremities (excluding hands and feet); treatment area should include 1 cm margin of skin around tumor
• Aldara 5%: Apply 5 times a week for 6 weeks to biopsy-confirmed superficial basal cell carcinoma and include 1 cm margin of skin around tumor

External Genital Warts

• Indicated for the treatment of external genital and perianal warts/condyloma acuminata
• Zyclara 3.75%: Apply as thin film to entire treatment area and rub in until cream is no longer visible; may wash with mild soap and water after 8 hours of application; use 1 packet or 1 full actuation of pump
• Aldara 5%: Apply 3 times a week until total clearance of warts or for a maximum of 16 weeks; examples of application schedules are Monday, Wednesday, Friday or Tuesday, Thursday, Saturday; use 1 packet only for each application

Dosing Considerations

• Zyclara can be used daily on larger surface areas than Aldara
• Actinic keratosis: Do not extend specified treatment cycle due to missed doses or rest periods

Pediatric:

External Genital Warts

Indicated for the treatment of external genital and perianal warts/condyloma acuminata

< p style="text-align:justify">Children 12 years: Safety and efficacy not established

Children 12 years and above

• Zyclara 3.75%: Apply as thin film to entire treatment area and rub in until cream is no longer visible; may wash with mild soap and water after 8 hours of application; use 1 packet or 1 full actuation of pump
• Aldara (5%): Apply 3 times a week until total clearance of warts or for a maximum of 16 weeks; examples of application schedules are Monday, Wednesday, Friday or Tuesday, Thursday, Saturday; use 1 packet only for each application

Administration

• External genital warts: Apply prior to normal sleeping hours and leave on skin for approximately 8 hours; then wash with mild soap and water; non-occlusive dressings such as cotton gauze/underwear may be used in management of skin reactions

Overdose

• Topical imiquimod overdose can cause an increased incidence of severe local skin reactions and also increase the risk for systemic absorption and reactions.
• Oral overdose of imiquimod was reported to have caused low blood pressure in a clinical trial, which resolved with fluid administration.

What drugs interact with imiquimod?

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

• Imiquimod has no known severe, serious, moderate or mild interactions with other drugs.

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.

Pregnancy and breastfeeding

• There are no adequate and well-controlled studies on the safety of imiquimod use in pregnant women. Imiquimod should be used in pregnancy only if potential benefits to the mother outweigh potential risks to the fetus.
• It is not known if imiquimod is excreted in breast milk. Use with caution in nursing mothers.

What else should I know about imiquimod?

• Apply imiquimod exactly as directed.
• Imiquimod is for topical application only. Avoid contact with eyes, lips and nostrils. Do not apply intravaginally.
• Avoid sun and sunlamps, and wear sun-protective clothing while using imiquimod, it can cause sunburn.
• Imiquimod may weaken condoms and vaginal diaphragms, use other methods of contraception.
• Store safely out of reach of children.
• In case of accidental ingestion or overdose, seek medical help or contact Poison Control.

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