Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The following side effects have been reported by at least 1% of people taking Zyclara (Imiquimod). Many of these side effects can be managed, and some may go away on their own over time.

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

• any sign or symptom in the treatment area that makes daily activity difficult or impossible
• any sign or symptom that makes it difficult to continue applying the medication
• chest pain
• Cold Sores
• flare up of herpes infection
• flu-like symptoms (e.g., Fever or chills, headache, muscle aches, nausea)
• painful joints
• rash
• symptoms of an infection (e.g., coughing, sore throat, muscle or joint pain, swollen glands, fatigue)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• severe diarrhea

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Zyclara (Imiquimod).

2.5%
Each gram of off-white to faintly yellow cream contains Zyclara (Imiquimod) 25 mg (2.5%). Nonmedicinal ingredients: isostearic acid, cetyl alcohol, stearyl alcohol, white petrolatum, polysorbate 60, sorbitan monostearate, glycerin, xanthan gum, purified water, benzyl alcohol, methylparaben, and propylparaben.

3.75%
Each gram of off-white to faintly yellow cream contains Zyclara (Imiquimod) 37.5 mg (3.75%). Nonmedicinal ingredients: isostearic acid, cetyl alcohol, stearyl alcohol, white petrolatum, polysorbate 60, sorbitan monostearate, glycerin, xanthan gum, purified water, benzyl alcohol, methylparaben, and propylparaben.

Do not use Zyclara (Imiquimod) if you are allergic to Zyclara (Imiquimod) or any ingredients of the medication.

There may be an interaction between Zyclara (Imiquimod) and any of the following:

• corticosteroids (e.g., Prednisone)
• echinacea
• Leflunomide
• live vaccines (e.g., BCG, yellow fever)
• medications that suppress the immune system (such as medications for cancer or organ transplants, e.g., Tacrolimus, Cyclosporine, Methotrexate)
• Natalizumab
• Pimecrolimus
• other medications applied to the skin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Zyclara (Imiquimod). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Zyclara (Imiquimod).

Exposure to sunlight: You should avoid or minimize any exposure to sunlight (including sunlamps) and use protective clothing (such as long sleeves and a hat) during treatment with Zyclara (Imiquimod) cream due to an increased risk of Sunburn. If you get a sunburn, stop using the medication until you are fully recovered.

Immunosuppressed individuals: The safety and effectiveness of Zyclara (Imiquimod) cream has not been determined for people with medical conditions affecting the immune system (e.g., HIV/AIDS, Lupus, psoriasis) or people taking medications that reduce the effectiveness of the immune system. If you have any condition affecting the immune system, discuss with your doctor how Zyclara (Imiquimod) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Zyclara (Imiquimod), and whether any special monitoring is needed.

New actinic keratosis (AK) lesions: During treatment with Zyclara (Imiquimod) cream, new AK lesions may develop, but may clear with treatment. Even though initial AK lesions disappear with treatment, new lesions may develop in the future and will require further treatment. Keep in mind that AK is considered to be a chronic skin condition, and Zyclara (Imiquimod) cream is not a cure.

Skin colour changes: Some people using Zyclara (Imiquimod) cream notice that the area where the cream was applied has become lighter or darker. Sometimes, the change in skin colour is permanent.

Skin reactions: If you experience a severe skin reaction to this cream, wash the area with mild soap and water. Once the reaction has cleared, start using the cream again, unless your doctor has told you to stop using it.

Pregnancy: Zyclara (Imiquimod) should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Zyclara (Imiquimod), contact your doctor immediately.

Breast-feeding: It is not known if Zyclara (Imiquimod) passes into breast milk. If you are a breast-feeding mother and are taking Zyclara (Imiquimod), it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using Zyclara (Imiquimod) have not been established for children under 18 years of age.