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HealthInfo Canterbury

Treating severe acne

If your acne is severe or isn't getting better with treatment, your doctor may advise that you try a medicine called isotretinoin.

Isotretinoin comes in capsules, brand names include Oratane and Isotane.

Isotretinoin is very effective for treating acne. It works by reducing the amount of sebum (oil) produced, shrinking the oil-producing glands (sebaceous glands) and reducing the number of bacteria on the skin, as well as having anti-inflammatory properties, reducing redness and inflammation.


If you're pregnant or might get pregnant, you mustn't take isotretinoin as it can cause miscarriages and severe birth defects. If you're a woman of child-bearing age and are considering taking isotretinoin, you'll need a negative pregnancy test (preferably a blood test) in the two weeks before starting the medication. You'll also need to take two forms of contraception for a month before taking isotretinoin, during treatment, and for one month after stopping it. Discuss this with your GP.

Risks or possible complications of isotretinoin

Isotretinoin has a number of side effects so it isn't suitable for everyone.

Not all GPs prescribe isotretinoin. If your GP isn't comfortable prescribing it for you, they may refer you to another GP with more experience in prescribing it or to a doctor who specialises in skin conditions (a dermatologist).

Before starting isotretinoin you'll be asked to sign a consent form that states you understand the risks. You will also need a blood test which includes:

Monitoring while on isotretinoin

Because of the possible side effects and risk to pregnant women, if you're taking isotretinoin you'll need to see your doctor regularly to monitor your health. You'll need a repeat blood test after one month of treatment then every three months after that.

Your GP will also want to see you regularly to check how your skin is responding and ensure you're managing any side effects. They'll ask about your mood and check for signs of depression.

If you're a woman of child-bearing age, you'll need to have a pregnancy test before starting isotretinoin, one month after starting, monthly during treatment and again five weeks after treatment.

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Written by HealthInfo clinical advisers. Last reviewed August 2021.


Page reference: 37456

Review key: HIACN-20774