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Treating severe acne with isotretinoin

If your acne is severe or not getting better with treatment, your general practice team may suggest trying isotretinoin.

Isotretinoin comes in capsules. Brand names include Oratane and Isotane.

Isotretinoin is very effective. It reduces the amount of oil (sebum) produced in your skin and shrinks the oil-producing glands (sebaceous glands). It also reduces the number of bacteria on your skin.

Isotretinoin has anti-inflammatory properties, which reduces redness and inflammation. Acne usually improves within 1 to 2 months of starting isotretinoin.

You need to take isotretinoin until no new spots are forming (usually 3 to 5 months). Then for another 2 to 4 months to reduce the risk of your acne getting worse again.

Precautions while taking isotretinoin


If you are pregnant or might get pregnant, you must not take isotretinoin. This is because it can cause miscarriages and severe birth defects.

If you are a woman of child-bearing age, you will need a negative pregnancy test. This should be in the two weeks before starting isotretinoin.

You will also need to use two forms of contraception. This is necessary for a month before taking isotretinoin through to one month after stopping it.

Discuss this with your general practice team.

Monitoring while taking isotretinoin

You will need to have a blood test before starting isotretinoin. This is to check your liver function and blood fats (triglycerides).

Your general practice team will want to see you to check how your skin is responding. They will also want to make sure you are managing any side effects.

You will need a repeat blood test after about 2 months of treatment.

You may need repeat pregnancy tests.

Side effects from isotretinoin

Isotretinoin can cause unwanted side effects, which include:

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Written by HealthInfo clinical advisers. Last reviewed August 2021. Last updated November 2023.


Page reference: 37456

Review key: HIACN-20774