Isotretinoin is a vitamin A derivative that belongs to the class of medications called retinoids. Retinoids are typically used to treat skin problems. Isotretinoin is used to treat severe types of acne, such as nodular or inflammatory acne, where other medications with less potential for severe side effects have failed to help. It may also be used to treat acne conglobata and recalcitrant acne.

Isotretinoin helps to reduce sebum production, which is often associated with bacteria that contributes to acne. In many cases, it can produce remission of the acne condition.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The usual starting daily dose is 0.5 mg per kilogram of body weight taken daily for a period of 2 to 4 weeks. Based on body weight, severity of acne, and your response to the medication, your doctor will then adjust your dose. Isotretinoin should be taken as a single dose or in 2 divided doses during the day.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Your acne may get worse temporarily, before it gets better. Your doctor will adjust your daily dose after the initial treatment depending on your response to the medication.

Food increases the amount of medication available to the body. It also helps to reduce upset stomach. For these reasons, isotretinoin medication should be taken with food.

The first signs of healing usually occur after 2 to  3 weeks of treatment, however, it may take 1 or 2 months before you see beneficial effects. The complete course of treatment usually lasts 12 to 16 weeks. Most people with severe acne notice a marked improvement after 1 or 2 courses of treatment. You may continue to see even more improvement in your acne condition for several months after you have stopped taking the medication.

If any of your side effects do not clear up in a few weeks after you stop taking your medication, speak to your doctor. Be sure to read the patient information that comes with each package of medication.

It is important that this medication be taken exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, in the original package, protect it from light and moisture, and keep it out of the reach of children.

10 mg
Each oval capsule with a yellow to orange paste fill and a reddish-brown opaque gelatin shell, with an "I" logo printed in black ink on one side, contains 10 mg of isotretinoin. Nonmedicinal ingredients: ammonium hydroxide, beeswax yellow, gelatin, glycerin, hydrogenated vegetable oil, polyethylene glycol, polyvinyl acetate phthalate, propylene glycol, red iron oxide, soybean oil, synthetic black iron oxide, and titanium dioxide.

40 mg
Each oval capsule with a yellow-to-orange paste fill and an orange-brown opaque gelatin shell, with an "I40" logo printed in black ink on one side, contains 40 mg of isotretinoin. Nonmedicinal ingredients: ammonium hydroxide, beeswax yellow, gelatin, glycerin, hydrogenated vegetable oil, polyethylene glycol, polyvinyl acetate phthalate, propylene glycol, red iron oxide, soybean oil, synthetic black iron oxide, titanium dioxide, and yellow iron oxide.

Do not take isotretinoin if you:

• are allergic to isotretinoin or any ingredients of the medication
• are breast-feeding
• are pregnant
• are taking tetracycline antibiotics (e.g., tetracycline, doxycycline, minocycline)
• have excessively high blood cholesterol levels
• have excessively high levels of vitamin A
• have reduced kidney or liver function

Isotretinoin should not be taken by women who may become pregnant unless all of the following conditions apply:

• You have severe disfiguring nodular or inflammatory acne, acne conglobata, or recalcitrant acne that has not responded to standard therapy, including systemic antibiotics.
• You are reliable in understanding and carrying out instructions.
• You have a negative pregnancy test before each 30-day prescription of medication and an additional test, one month after stopping isotretinoin.
• You are able to comply with the mandatory birth control measures for at least one month before, during, and at least one month after treatment.
• You have received, and acknowledged understanding of, a careful oral and printed explanation of the hazards of fetal exposure to isotretinoin, and the risk of possible birth control failure.
• You have been informed and understand the need to quickly consult your doctor if there is a risk that you may be pregnant.
• You understand the need for monthly follow-up.
• You use effective birth control without any interruption for one month before, during, and for one month after stopping isotretinoin. You are aware that 2 reliable forms of birth control should be used at the same time.
• You have had a blood or urine pregnancy test with a negative result, performed in a licensed laboratory, within 2 weeks prior to initiating therapy. You have had 2 or 3 days of your next normal menstrual period before isotretinoin therapy is initiated.
• If you require additional treatment with isotretinoin in the future, you must also follow the same requirement for birth control before, during and after taking isotretinoin.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• difficulty in wearing contact lenses (may continue after treatment is stopped)
• dry eyes (may continue after treatment is stopped)
• dry or itchy skin
• dry mouth or nose
• flaking skin
• increased sensitivity of skin to sunlight
• nosebleeds
• peeling of skin on palms of hands or soles of feet
• stomach upset
• thinning of hair (may continue after treatment is stopped)
• unusual tiredness

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• bleeding or inflammation of gums
• blurred vision or other changes in vision
• bone or joint pain or fractures
• burning, redness, itching, or other signs of eye inflammation
• changes in behaviour
• decreased hearing
• decreased vision after sunset or before sunrise (sudden or may continue after medication is stopped)
• ringing in the ears
• scaling, redness, burning, pain, or other signs of inflammation of lips
• signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• pain, tenderness, or stiffness in muscles (long-term treatment)
• rash on the face or body
• signs of heart problems (e.g., fast, irregular heartbeat or pulse, chest pain, sudden weight gain, difficulty breathing, leg swelling)
• signs of increased pressure in the brain (e.g., bad headaches, blurred vision, dizziness, nausea, vomiting, seizures)
• signs of inflammatory bowel disease (e.g., severe abdominal or stomach pain, severe diarrhea, rectal bleeding)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• signs of muscle damage (e.g., unexplained muscle pain, tenderness or weakness, or brown or discoloured urine)
• skin infection or rash
• symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• attempts at suicide or thoughts of suicide
• signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
• signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Behaviour changes and suicidal thoughts: Some people taking this medication have experienced depression, including thoughts of suicide. If you experience any behaviour change or symptoms such as sad mood, hopelessness, feelings of guilt, loss of pleasure or interest in activities, changes in sleep pattern, irritability, or restlessness while taking this medication, contact your doctor immediately.

If you are at risk for developing depression or have a history of depression, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Family members or caregivers of people who are taking this medication should contact the person's doctor immediately if they notice unusual behaviour changes.

Birth control: Isotretinoin causes birth defects in a large percentage of babies born to people who take this medication during pregnancy. Isotretinoin interacts with hormonal birth control (i.e., birth control pills), making it very important that people of childbearing age use an additional type of birth control.

Two reliable forms of birth control should be used at the same time during treatment unless abstinence is the chosen method. Birth control must be used for at least one month before starting isotretinoin, during treatment with this medication and for at least one month after stopping the isotretinoin.

Blood donation: You should not give blood during treatment with isotretinoin and for one month after stopping treatment in case the blood is given to a pregnant people.

Bones and joints: Isotretinoin may cause some minor bone changes. Talk to your doctor if you notice aches or pains in the bones or joints, or have difficulty moving. Your doctor may monitor you for bone changes while you are taking this medication.

Cholesterol: Isotretinoin can cause increases in cholesterol and other lipids in the blood. If you are already at an increased risk of developing high cholesterol, for example if you have a family history of high cholesterol, diabetes, are overweight, or have an increased alcohol intake, you are more likely to experience this.

If you are at any increased risk of developing increased blood lipids, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Contact lenses: This medication may cause dry eyes. If you use contact lenses you may find them uncomfortable to wear. You can help manage dry eyes by using a lubricating eye ointment or replacement tears.

Diabetes: Isotretinoin may cause a loss of control of blood sugar levels for people with diabetes. If you have diabetes, or anyone in your family has diabetes, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. You may need to check your blood glucose levels more often.

Inflammatory bowel disease: This medication may cause irritation in the digestive system. If you experience stomach pain, rectal bleeding or diarrhea, contact your doctor immediately.

Liver disease: Several cases of hepatitis (inflammation of the liver) have been reported that are considered to be possibly or probably related to isotretinoin therapy.

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Muscle effects: There have been reports of muscle damage associated with use of isotretinoin, especially after strenuous physical activity. Report any unexplained muscle pain, tenderness, weakness or cramps, or any brown or discoloured urine to your doctor immediately, particularly if you are also experiencing malaise (a general feeling of being unwell) or fever.

Neurologic: Isotretinoin has been linked to causing intracranial hypertension, also known as pseudotumor cerebri. Early symptoms of this condition include headache, nausea, vomiting, and visual disturbances. If you have these symptoms call your doctor immediately.

Night vision: Decreased night vision has been reported during isotretinoin therapy. Because some patients experience sudden onset of vision problems, use caution when driving or operating any vehicle at night. Report any vision changes to your doctor.

Pancreatitis: Isotretinoin can cause the pancreas to become inflamed. If you have a history of pancreatitis, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Report signs of pancreatitis such as abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, or swollen abdomen to your doctor immediately.

If you have a history of pancreatitis, gallstones, alcoholism, or high triglycerides, you may be more at risk of experiencing this.

Skin care: Isotretinoin causes irritated, dry skin and lips. Ask your doctor or pharmacist for appropriate moisturizers and lip balms to use to prevent severe dryness. While you are taking isotretinoin, avoid exfoliators, waxing and dermabrasion, or laser procedures.

Skin rash: Isotretinoin may cause skin rash or itchiness. Rarely, people taking isotretinoin experience a severe skin reaction that can be life threatening. If you experience a rash that gets worse, or develops into blisters, sores on the lips or eyes, or covers a large area of the body, contact your doctor immediately.

Sun sensitivity: Isotretinoin may make you more likely to burn in the sun. Use appropriate measures to prevent excessive exposure to the sun. These include wearing a hat and sunglasses when out in the sun, using a sunscreen that provides an SPF of 15 or more, and avoiding going out in the sun between 10 am and 2 pm when the sun is at its strongest.

Vitamin supplements: You should not take vitamin supplements containing vitamin A if you also take isotretinoin as this may increase the side effects of vitamin A. Talk to your doctor or pharmacist if you are not sure which of your supplements might contain vitamin A.

Pregnancy: Isotretinoin causes severe birth defects in an extremely high percentage of infants born to people who take this medication even for a short period of time during pregnancy.

Isotretinoin must not be used during pregnancy. People must not become pregnant while taking isotretinoin or for at least one month after stopping the medication. Your doctor will perform monthly pregnancy tests while you are taking isotretinoin to confirm the safety of continuing to take this medication.

People who may become pregnant must not be given isotretinoin until pregnancy is excluded. A pregnancy test should be performed when you first see your doctor. A second pregnancy test must be performed within 11 days of starting treatment. Isotretinoin treatment should start on the second or third day of the next normal menstrual period following this negative pregnancy test. Effective birth control must be used for at least one month before starting isotretinoin treatment, during the treatment, and for at least one month following the discontinuation of treatment.

Breast-feeding: It is not known if isotretinoin passes into breast milk. If you are breast-feeding and taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding. Because of the potential for side effects, people should consider not breast-feeding if they take isotretinoin.

Children: The long-term safety of using this medication have not been established for children less than 12 years of age.

Seniors: The use of isotretinoin by seniors has not been well studied. It is likely that seniors would be at an increased risk for side effects from this medication.

For a full list of interactions, use the Drug Interaction Checker available on the Drugs.com website.

If you are taking other medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.