Imiquimod Reviews: Efficacy, Side Effects, and Alternatives

Imiquimod is a prescription cream that doesn’t attack a growth directly. It prompts the immune defences in your skin to destroy it. That’s why one cream is used for quite different problems: precancerous sun damage, an early surface skin cancer and genital warts, and how well it works depends on which one you have. The inflamed, raw-looking skin many users describe in reviews is usually the treatment working, not a sign it has gone wrong.¹ It is rarely the only choice, though, and for skin cancer surgery remains more reliable.²

How Well Imiquimod Clears Sun Spots

Actinic keratoses are rough, scaly patches caused by years of sun exposure, most often on the face, scalp, hands and forearms. A small share can turn into squamous cell carcinoma, a type of skin cancer, so treating them lowers that risk.³

After 12 to 16 weeks, about half of people using the 5% cream are completely clear, compared with 1 in 20 using a cream with no drug in it.⁴ With one or two 4-week courses on the head, about 7 in 10 people cleared completely and 8 in 10 lost at least three-quarters of their spots.⁵ People with very large areas of damage, averaging about 45 spots, cleared completely only about a third of the time, even though their spot count fell by about 80%.⁶

Complete clearance means no visible spots remain in the treated area; partial clearance means at least three-quarters are gone. Sun-damaged skin can grow new spots later, so regular skin checks continue either way.

The cream is spread over the whole patch of skin, not just onto individual spots, so it reaches areas beyond what you can see. Early damage nearby that was invisible before can turn red and scaly as the immune response reaches it. These newly visible spots are usually being cleared along with the rest, so more spots appearing in the first weeks is not usually a sign of failure. If many new spots appear and none fade after the rest weeks, mention it at your follow-up.

Spots can keep clearing during the rest weeks between cycles, after the inflammation has calmed down.⁷ So judge results a few weeks after a cycle ends, not on the last day of application.

Imiquimod for Basal Cell Carcinoma

Superficial basal cell carcinoma is a slow-growing skin cancer that sits in the top layer of skin, often appearing as a flat, pink, scaly patch. About 9 in 10 superficial BCCs showed no visible tumour 12 weeks after a course of imiquimod.⁸ Some came back, and when they did it was mostly within the first year.⁹ About 8 in 10 treated patients were still clear after 5 years.¹⁰

Because the cancer sits in the top layer, the cream can reach all of it, which is why this type responds better than deeper types. The patch typically turns red and crusted as the immune attack proceeds, and the crust may seem larger than the original spot. A pink, flat area can remain once the crust falls off, and that does not by itself mean the cancer is still there. Your doctor may check the site after treatment, and sometimes a small sample is taken if it is unclear whether any cancer remains.

In a large trial, imiquimod succeeded over 5 years for about 82% of people, compared with about 98% for surgery.¹¹ People rated the appearance of their skin about the same after either treatment.¹² So imiquimod suits small, low-risk BCCs when you prefer to avoid surgery, have several lesions, or the spot is in an awkward place to cut.¹³ Most failures show up in the first year, so watch for a pink patch, scab or sore returning at the same site and report it.

Imiquimod for Genital Warts

About half of people using imiquimod for external genital warts clear completely by the end of treatment, compared with about 6% using a dummy cream.¹⁴ Among people whose warts cleared, about 16% had new warts within 3 to 4 months.¹⁵ Most recurrences show up within the first 3 months.¹⁶ With longer follow-up recurrence rises, reaching about 41% at 12 months in one study.¹⁷ Only about 37% of people both clear and stay clear in the months after treatment.¹⁸

Warts return because the virus that causes them can remain in nearby skin after the visible warts are gone. A recurrence may be the old infection or a new one from a partner. It doesn’t mean the cream failed, and it can be treated again. Condoms reduce but don’t fully prevent spread, because the virus lives on skin outside them.

In the months after treatment, check the area regularly for new small bumps, especially in the first 3 months. If warts reappear, return early rather than waiting for a scheduled visit. Tell your doctor if your partner has warts, since reinfection is possible.

Imiquimod for warts is meant for external warts on the skin of the genital and anal area. It is not for warts inside the vagina, urethra or anal canal, so ask your doctor where you may apply it. Warts in those internal areas usually need an in-office treatment instead.

Side Effects You Can Expect on Your Skin

Common reactions where the cream is applied include redness, itching, burning, blisters, raw or weeping skin, scabbing and lighter patches of skin.¹⁹ Itching and weeping were the most common complaints in a large skin-cancer trial.²⁰ This skin reaction is the main side effect.

The cream switches on immune sensors in skin cells, which release signals that call in immune cells to attack abnormal or infected cells.²¹ The redness and crusting are signs of that attack.²² More redness, raw skin and scabbing tended to go with higher clearance rates.²³

Reactions tend to build with each cycle and return to normal during rest periods.²⁴ In people treated after surgery, extra redness and colour changes faded with time.²⁵

The first week may show little change. By weeks two to three the area often turns red, rough and crusted. Raw or weeping patches may follow, and the area can look worse than it did before you started. Healing starts within days of stopping or resting, and skin usually settles in a few weeks.

Wash the area gently and avoid scrubbing off scabs. A plain moisturiser can ease dryness, but ask before using other creams on the area. Protect it from sun during and after treatment, and ask your doctor before covering it with a tight bandage.

Redness, crusting and soreness limited to the treated area are expected, but pain that keeps you from sleeping or daily tasks is worth reporting. Skin reddening that spreads well beyond the treated patch, or oozing pus, may signal infection rather than treatment effect. In those cases, call your doctor, who may advise pausing the cream or treating an infection.

Flu-Like Symptoms and Rare Reactions

Flu-like symptoms such as tiredness, aches, chills or mild fever are less common than skin reactions but can occur.²⁶ They tended to appear alongside strong skin reactions, especially when treating the face or scalp.²⁷ They usually ease during rest weeks along with the skin reaction.²⁸

These symptoms are more likely when a large area is being treated, so ask your doctor about them if you are treating a wide area or several spots. Rest and plenty of fluids help, and your doctor or pharmacist can advise whether a common pain or fever reliever is suitable for you. If symptoms are bothersome, ask whether to skip a dose or take a rest day, because pausing usually settles them.

Rarely, the immune activation can lead to white patches like vitiligo that may not fade.²⁹ This has been reported after treating genital warts and may be more likely in people with a genetic tendency.³⁰ Mention any personal or family history of vitiligo or autoimmune disease before starting.

How Imiquimod Is Used and Why Rest Breaks Help

Lower-strength creams for sun spots are often used daily for 3 weeks, then rested for 3 weeks, then used again for 3 weeks.³¹ For BCC, treatment lasted about 16 weeks on average, from 6 to 28 weeks.³²

About 1 in 4 people using the 3.75% cream needed a short pause because of reactions, yet few stopped altogether.³³ A pause does not ruin the treatment, since clearing continues during rest weeks.³⁴ If the skin gets too sore, ask your doctor about pausing rather than quitting.

Apply a thin layer to the prescribed area at bedtime and wash it off after the time your prescription states. Wash your hands before and after. Use only as many packets or pumps as prescribed, because more does not work faster. Keep the cream away from eyes, lips and nostrils.

The 5%, 3.75% and 2.5% creams have different schedules that aren’t interchangeable. The lower strengths allow treating a wider area daily for shorter periods. Follow the schedule on your own prescription, not another person’s.

If you miss an application, do not double up the next time; carry on with the usual schedule. The cream stays on for a set number of hours, so check your leaflet or ask the pharmacist if you are unsure.

Alternatives to Imiquimod

For sun spots, light-activated treatment (photodynamic therapy) works about as well as imiquimod with similar cosmetic results.³⁵ People were more satisfied with it than with imiquimod in one comparison.³⁶ In the UK, imiquimod costs less than photodynamic therapy over a year.³⁷ In photodynamic therapy, a light-sensitising cream is applied and left for a period, and then a special light is shone on the area. Many people feel stinging or burning during the light, and the skin then becomes red and crusted for a time. You usually need to stay out of strong sunlight for a day or two afterwards. Using imiquimod right after freezing thick sun spots cleared more spots than freezing alone,³⁸ because freezing loosens the skin so more cream gets in.³⁹

For genital warts, the options compare like this:

Sinecatechins: an ointment made from green tea, about 57% clear, with the fewest recurrences of any cream, about 7%.⁴⁰
Podofilox: about 45% clear, but about 38% recur.⁴¹
Freezing: about 75% clear, but about 40% recur.⁴²
Imiquimod: clears about half, with fewer recurrences than podofilox or freezing.⁴³

For BCC, surgery remains the most reliable option.⁴⁴ Fluorouracil is a cream applied for a number of weeks, and like imiquimod it makes the skin red, crusted and sore. It works directly on abnormal cells rather than through the immune system.

Using Imiquimod With a Weakened Immune System or in Children

Transplant recipients, who have a higher risk of sun spots, cleared completely about 62% of the time with imiquimod.⁴⁵ No one had organ rejection and their medicines didn’t need adjusting.⁴⁶

Anti-rejection medicines weaken the immune system, which is why sun spots and skin cancers are more common after a transplant. Treatment still belongs under the care of a doctor who knows your history. Tell them your transplant type and current anti-rejection medicines, and ask whether your transplant team should be informed before you start. Report fever or feeling unwell promptly, since flu-like side effects can be hard to tell apart from infection.

Imiquimod isn’t approved for children under 12, though it was well tolerated for molluscum, a common skin infection in children, in a small study.⁴⁷ If it is recommended for a child, ask the doctor why and what the alternatives are.