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Isotretinoin Therapy Information

You have been prescribed a course of Isotretinoin for your acne. This information should be read together with the patient information leaflet by the manufacturer of this product.


What is Isotretinoin?

This is a drug which is used to treat and cure acne. The drug is only available from a Dermatology consultant on prescription. The drug needs to be taken for a specified length of time, which will be explained to you by your doctor.

How is it given?

The capsules should be taken by mouth once a day. Always make sure that you take the capsule on a full stomach and never on an empty stomach.

Is there anything I should avoid?

-        Avoid alcohol completely, or only drink small quantities of alcohol, during the treatment course.
-        Do not take vitamin A supplements in the form of oral or powder multivitamins.
-        Do not take certain prescribed medicines such as Tetracyclines (eg Oxytetracycline, Lymecycline, Doxycycline, Minocycline) or Methotrexate.

Are there any side-effects?

Very common side effects include dryness to the face, arms, hair, throat, lips and eyes. The skin is more fragile, so wound and cuts take longer to heal and removing hair by waxing should be avoided.

-        You are twice as likely to burn in strong sunshine. This is less of a problem once you have acquired a protective suntan.

-        You will not be able to give blood.

-        If you are female, you must not become pregnant whilst on this tablet and for 3 months afterward you have stopped the tablet, as you will have a malformed baby and would be strongly recommended to have a termination of the pregnancy. Effective contraception is strongly recommended in fertile women with male partners. Equally men should not attempt to father a child whist on isotretinoin.

-        Women’s periods also become irregular on this treatment.

-        Skin and nail infections are more common on this treatment.

-        Muscles and joints can ache. This is much more likely if you do a lot of exercise, or the older you are when you take this treatment.

-        Less common, or rare side-effects include a decrease in night vision, a rise in cholesterol or triglycerides, inflammation of the liver or pancreas, temporary hair thinning, in-growing toe and fingernails and precipitation of gout attack.

-        A very rare side-effect, known as benign intra-cranial hypertension, can also occur. This presents with vomiting, a severe early morning headache and blurred vision.

-        Inflammatory bowel symptoms can be worsened or triggered.

Your doctor will tell you which side0effects you are more likely to suffer from and which ones are extremely unlikely. If the dosage of tablets is reduced or stopped completely, the side-effects will go away. Make sure you talk to your doctor before making any changes to your medication, if you are suffering from any symptoms.

Flare of acne

This can happen to one in ten people that start isotretinoin. The flare is no worse than a flare of your typical acne and settles with 4 weeks. It is not related to your starting dose of medication. Very rarely a severe inflammatory reaction that mimics severe acne can happen. This is usually controlled by adding in oral steroid tablets alongside a reduced dose of isotretinoin.

Mood changes

Because acne causes low self-esteem and depression, it is common to see patients develop depression before or after starting isotretinoin. Unrelated depressive mood changes have been reported after starting isotretinoin. It remains uncertain if these reports are co-incidental or related to the medication. If you have any mood changes, you should report these to your doctor, GP, friends and family.

Effects on sexual activity

Very rarely a wide variety of symptoms have been reported including reduced libido. Not many cases have been reported, and only in the last few years. These symptoms can start during or after completing a course of treatment and can persist.

Peanut or Soya Allergy

Isotretinoin is contra-indicated in those with a known peanut or soya allergy. Peanuts share proteins with soya. Soya allergy is against soya protein and not soya oil. Isotretinoin capsules contain soya oil. Any soya protein within the capsules is either heavily modified or absent. The risk of having an allergic reaction is therefore theoretical rather than likely. Your doctor may wish to carry out further investigations to establish if you have a Type 1 allergy to peanut or soya and may wish to start your treatment in the clinic rather than at home.

Blood tests

You will need one blood test before you start treatment and at least one blood test approximately six weeks into treatment. It is very rare to require any further blood tests. These blood tests will be 9am fasting samples (no food or drink except for water from 9pm the night before the blood test).

What are the risks of having treatment or not having treatment?

There are no long-term risks of having treatment. All side-effects will go away once the treatment is stopped. The treatment course must be completed in full, otherwise a successful cure of your acne will not happen.

What are the benefits?

There is a 95% (95 out of 100) chance of you curing your acne with a single course of at least 4 months at a dose of 1mg/kg per body weight per day. Course extensions may be required if you are still spotty after 4 months treatment.

There is a 60% chance of curing your acne if you are older than this.

Lower dosage courses have a reduced chance of curing your acne or not curing you at all.
Please note that isotretinoin is also prescribed by Dermatologists for other types of skin conditions using different dosages and protocols.

Are there any alternatives to this medication?

There are no known alternative acne cures.

Other medications

Please tell your doctor if you are on any other medications or supplements before you start treatment, or if you start anything during treatment.

What if there is a problem with taking the medication?

The capsules need to be swallowed whole and cannot be crushed or split open. If you miss your dose that day, do not take a double dose on the next day.

You need to finish all the tablets that have been given to you. By missing a dose, your treatment course will be one day longer.

Storing your medication

Store the tablets in a cool, dark place. Keep these capsules away from children.

Repeat prescriptions

Your GP cannot prescribe you this drug. This drug is only available from a consultant Dermatologist.

Who can I call if I have any problems?

You will be reviewed at least once during your treatment course. Questions and problems can be discussed at this consultation. Most problems regarding this medication can be discussed over the phone or by email.

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