Imiquimod cream (Aldara)

Imiquimod cream is a cancer treatment and is also known by its brand name, Aldara. 

It is a treatment for:

  • basal cell skin cancer (BCC)
  • a skin condition called actinic (solar) keratosis

Basal cell skin cancer (BCC)

Imiquimod cream is approved in the UK for the treatment of superficial basal cell skin cancers measuring up to 2cm across. It can be used on your chest, neck, arms or legs (including hands and feet). It is not approved for a type of BCC called nodular BCC. 

Actinic (solar) keratosis

This skin condition might develop into squamous cell skin cancer. So you usually have treatment.


Occasionally, imiquimod is used as a treatment for melanoma skin cancer.

How it works

Imiquimod cream uses your body’s natural defences to help kill the skin cancer cells. It works by releasing a number of chemicals called cytokines. One of these cytokines is called interferon.

Interferon is a protein that the body makes as part of the immune response. Interferon is also used as a cancer treatment. It is thought that imiquimod makes cells produce more interferon which destroys the skin cancer cells.

When you have it

To treat BCC, you usually put imiquimod cream on to the affected area once a day, 5 days a week for 6 weeks. You usually leave the cream on the skin for about 8 hours. You shouldn't shower or bathe during this time. 

Side effects

How often and how severe the side effects are can vary from person to person. They also depend on what other treatments you're having. For example, your side effects could be worse if you're also having other drugs or radiotherapy.

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you closely during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

  • you have severe side effects 
  • your side effects aren’t getting any better
  • your side effects are getting worse

Early treatment can help manage side effects better. 

Contact your doctor or nurse immediately if you have signs of infection, including a temperature above 37.5C or below 36C.

We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects, but you might have some of them at the same time.

Common side effect

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Itchy skin

You can get itchy skin in the treatment area soon after starting this treatment.

Let your doctor or nurse know if you have this.

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:

  • infections
  • pustules - small bumps on the skin that contain fluid or pus
  • enlarged lymph nodes
  • back pain
  • problems at the application site including pain, redness, rash, burning, bleeding, tingling, prickling, bumps

Rare side effects

These side effects happen in fewer than 1 in 100 people (fewer than 1%). You might have one or more of them. They include:

  • feeling moody and irritable
  • feeling sick
  • dry mouth
  • inflammation of the skin
  • flu like symptoms
  • at the site of application swelling, leaking fluid, inflammation, scabs, small cyts, breakdown of the skin
  • tiredness and lacking energy

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

Other medicines, food and drink

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.

Contraception and pregnancy

It is not known if this treatment can harm a developing baby in the womb. Talk to your doctor or nurse about effective contraception. 


It is not known whether this drug comes through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.

Treatment for other conditions

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment if you need treatment for anything else, including teeth problems.

More information about this treatment

For further information about this treatment go to the electronic Medicines Compendium (eMC) website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

Related links