Dermatology
Isotretinoin (oral)
High-strength vitamin-A capsule for severe acne — A powerful oral treatment that can clear severe acne — with strict pregnancy-prevention rules.
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
Quick answer
What is Isotretinoin (oral)?
Isotretinoin is a strong vitamin-A-derived capsule used for severe or scarring acne that has not responded to other treatments. It is started and supervised by a specialist and can give long-term clearance after one course.
- How it works: It shrinks the skin's oil glands and dramatically reduces oil production, normalises the shedding of pore-lining cells and reduces the acne bacteria and inflammation — tackling all the main drivers of acne at once.
- In practice: In practice oral isotretinoin is a highly effective, specialist-only treatment for severe, scarring or treatment-resistant acne, often producing long-lasting clearance after a single course.
What it is
Isotretinoin is a strong vitamin-A-derived capsule used for severe or scarring acne that has not responded to other treatments. It is started and supervised by a specialist and can give long-term clearance after one course.
How it works
It shrinks the skin's oil glands and dramatically reduces oil production, normalises the shedding of pore-lining cells and reduces the acne bacteria and inflammation — tackling all the main drivers of acne at once. This powerful effect on rapidly dividing cells is also why it harms a developing baby and dries the skin and lips.
In practice
In practice oral isotretinoin is a highly effective, specialist-only treatment for severe, scarring or treatment-resistant acne, often producing long-lasting clearance after a single course. Its use is dominated by one absolute rule: it causes severe birth defects, so anyone who could become pregnant must be in a pregnancy-prevention programme with reliable contraception and regular pregnancy tests before, during and after treatment. Beyond that, the practical themes are predictable, dose-related effects — very dry lips, skin and eyes, occasional nosebleeds, muscle aches and raised blood fats and liver markers, so lipids and liver function are checked. Sun sensitivity is increased. There has been long-standing discussion about mood, so people are asked to report low mood or thoughts of self-harm, and mental-health history is considered. Blood donation is avoided during and for a time after treatment. It is taken with food for absorption, and an early flare can occur before improvement.
Examples
Practical use
How to take it & use it well
- Take it with food, ideally a meal containing some fat, as this helps your body absorb it properly and makes it work better.
- If you can become pregnant, you must follow the pregnancy prevention programme, using reliable contraception and having regular checks, because this medicine causes serious harm to an unborn baby.
- Expect dry lips, skin and eyes, and use a good lip balm, moisturiser and, if needed, lubricating eye drops from the start to keep these manageable.
- Avoid waxing, harsh skin treatments and cosmetic skin procedures during treatment and for a while afterwards, as your skin becomes fragile and scars more easily.
- Protect your skin from the sun and avoid sunbeds, as this medicine makes you more likely to burn, and keep your blood tests up to date as arranged.
- Tell your prescriber straight away if you notice low mood, anxiety, or thoughts of harming yourself, as changes in mood must always be taken seriously and reported.
Common uses
- Severe, nodular or scarring acne
- Acne resistant to antibiotics and topical treatment
- Selected treatment-resistant rosacea (specialist)
Monitoring
- Pregnancy testing and contraception throughout the programme
- Lipids and liver function during treatment
- Mood and wellbeing; skin response and side effects
Weighing it up
Advantages & disadvantages
Advantages
- It is the most effective treatment for severe or stubborn acne and can clear skin that has not responded to anything else.
- Many people get a long-lasting improvement, and for some the acne does not return after the course.
- It can prevent the permanent scarring that severe acne often causes.
- It tackles the root causes of acne, reducing oil, blockage, bacteria and inflammation together.
- It is given under specialist supervision with regular monitoring to manage its risks.
Disadvantages
- It causes serious birth defects, so a strict pregnancy prevention programme is essential for anyone who could become pregnant.
- It very commonly causes dry, cracked lips, dry skin and eyes, and nosebleeds.
- Mood changes, including low mood and, rarely, thoughts of self-harm, must be watched for and reported.
- Acne can flare early in treatment, and the skin becomes more fragile and sun-sensitive.
- It requires regular blood tests and reviews, and is not suitable for everyone.
Key safety principles
What to watch for
- Causes severe birth defects — strict pregnancy prevention (reliable contraception and pregnancy testing before, during and after) is mandatory.
- Dose-related dryness of lips/skin/eyes, raised blood fats and liver markers — monitor lipids and liver function.
- Report low mood or thoughts of self-harm; avoid blood donation during and after; increased sun sensitivity.
Key interactions
What to avoid or check alongside
- It must not be taken with tetracycline antibiotics, as the combination can raise pressure inside the head and cause severe headaches and vision problems.
- Vitamin A supplements should be avoided, as this medicine is related to vitamin A and the effects can add up to harmful levels.
- Alcohol can add to its effects on the liver and on blood fats, so it should be limited and your bloods are monitored.
- Other medicines that dry the skin or affect the liver should be reviewed with your specialist before starting.
- Tell your team about all medicines and supplements, including anything bought without prescription, before and during treatment.
Patient & carer advice
- If you could become pregnant, you must use reliable contraception and attend pregnancy tests as required
- Expect dry lips and skin — use lip balm and moisturiser, and protect against sun
- Tell us promptly about low mood, and do not give blood while taking it
Answers
Isotretinoin (oral): frequently asked questions
Why is the pregnancy prevention programme so strict?
Isotretinoin causes serious harm to an unborn baby even from a small exposure, so anyone who could become pregnant must use reliable contraception and have regular pregnancy tests. The programme is there to make sure no one becomes pregnant while taking it or shortly after.
Can isotretinoin affect my mood?
Changes in mood, including low mood, anxiety and, rarely, thoughts of self-harm, have been reported. Tell your prescriber, family or a trusted person straight away if you notice your mood changing, and seek urgent help if you have thoughts of harming yourself.
Why are my lips and skin so dry on this medicine?
Dryness of the lips, skin, eyes and nose is one of the most common effects, because the medicine reduces the skin's oil. Use a good lip balm, moisturiser and lubricating eye drops from the start to keep it manageable.
Can I have my eyebrows waxed or get a facial during treatment?
It is best to avoid waxing, facials and other skin procedures during treatment and for a while afterwards, as your skin becomes fragile and can scar or be damaged more easily. Ask your specialist when it is safe to resume.
Will my acne come back after I finish the course?
Many people get a long-lasting improvement, and for some the acne does not return at all. Others may need further treatment, so your specialist will review your skin and discuss next steps if needed.
Authoritative sources
Always verify against the source
This overview is for orientation. For doses, interactions, contra-indications and the full monograph, use:
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