Tretinoin

What it is

• Tretinoin belongs to a class of medicines called retinoids.
• It is also known as retinoic acid and vitamin A acid.
• Tretinoin skin products come as a lotion, cream, and gel.
• Tretinoin for leukemia comes as a capsule taken by mouth.

Sources: MedlinePlus (NIH): Tretinoin Topical: MedlinePlus Drug Information ↗ · MedlinePlus (NIH): Tretinoin: MedlinePlus Drug Information ↗

How it's thought to work

On the skin, tretinoin works by increasing production of new skin cells and unclogging pores. In leukemia, it works by slowing or stopping the growth of cancer cells, by causing immature blood cells to develop into normal blood cells.

Sources: MedlinePlus (NIH): Tretinoin Topical: MedlinePlus Drug Information ↗ · MedlinePlus (NIH): Tretinoin: MedlinePlus Drug Information ↗

What people use it for

• Tretinoin applied to the skin is used to treat acne and to reduce fine wrinkles.
• It may reduce fine wrinkles but does not remove them or repair sun-damaged skin.
• Wrinkle improvement may take 3 to 4 months or up to 6 months.
• The Retin-A Micro gel label lists acne treatment in adults and children 12 and older.
• The capsules are used to produce remission of APL, but other medicines must be used afterward to prevent the cancer from returning.

Sources: MedlinePlus (NIH): Tretinoin Topical: MedlinePlus Drug Information ↗ · DailyMed (FDA drug label): DailyMed - RETIN-A MICRO- tretinoin gel ↗ · MedlinePlus (NIH): Tretinoin: MedlinePlus Drug Information ↗

What the research has found so far

Approved for sun-damaged skin after decades of trials.

On Tretinoin and aging, PubMed lists 107 trials in people, 42 studies that watched people over time, 53 animal and lab studies. See the counts and searches

Side effects and risks

• Skin forms may cause dryness, itching, burning, stinging, peeling, swelling, redness, blistering, or flaky skin where applied.
• Skin tretinoin can make the skin sensitive to sunlight.
• Using more than directed will not speed up results and may cause marked redness, peeling, or discomfort.
• Warning symptoms of RA-APL syndrome include fever, weight gain, swelling, shortness of breath, wheezing, chest pain, or cough.
• Capsules may raise blood cholesterol and other fats and may stop the liver from working normally.
• Other capsule side effects include weakness, extreme tiredness, shivering, pain, dry skin, rash, hair loss, constipation, diarrhea, stomach pain, heartburn, and loss of appetite.
• More capsule side effects include weight loss, bone pain, dizziness, numbness or tingling, nervousness, depression, trouble sleeping, confusion, agitation, hallucinations, trouble urinating, and flushing.
• Capsules may cause dizziness or severe headache.
• Swallowing tretinoin gel in large amounts may cause the same effects as too much vitamin A.
• In gel trials, irritation peaked in the first two weeks and then decreased.
• In one trial, 6% of people using the 0.1% gel stopped treatment because of skin irritation.

Sources: MedlinePlus (NIH): Tretinoin Topical: MedlinePlus Drug Information ↗ · DailyMed (FDA drug label): DailyMed - RETIN-A MICRO- tretinoin gel ↗ · MedlinePlus (NIH): Tretinoin: MedlinePlus Drug Information ↗

Who should be careful, and drug interactions

• Tretinoin capsules must not be taken by people who are pregnant or who may become pregnant.
• There is a high risk that capsules will cause birth defects.
• People who can become pregnant must use two forms of birth control during treatment and for 1 month after.
• Minipill birth control pills may not work well in people taking tretinoin capsules.
• Capsules should be given only under a doctor experienced in treating leukemia, in a hospital where severe side effects can be monitored.
• The capsule page says vitamin A may interact with tretinoin.
• People with high blood fats, or liver or heart disease, are told to tell their doctor before taking capsules.
• The capsule page says to talk to a doctor about grapefruit and grapefruit juice.
• Skin tretinoin should not go into the eyes, ears, mouth, nose corners, or vaginal area, or onto sunburned or eczema-affected skin.
• Benzoyl peroxide, hair removers, salicylic acid, and dandruff shampoos with sulfur or resorcinol may interact with skin tretinoin.
• Using acne products with benzoyl peroxide, sulfur, resorcinol, or salicylic acid may raise the risk of skin irritation.
• Weather extremes such as severe wind or cold may increase the risk of skin irritation.
• Studies in pregnant women using skin tretinoin have not established a risk of major birth defects or miscarriage, though the studies had limitations.
• In animal studies, high skin doses of tretinoin gel caused changes in offspring bones and malformations.

Sources: MedlinePlus (NIH): Tretinoin: MedlinePlus Drug Information ↗ · MedlinePlus (NIH): Tretinoin Topical: MedlinePlus Drug Information ↗ · DailyMed (FDA drug label): DailyMed - RETIN-A MICRO- tretinoin gel ↗

Approval and legal status

• FDA: DailyMed - RENOVA- tretinoin cream ↗

Amounts used in studies

What studies or labels describe, not a recommendation.

• Skin tretinoin is used daily at bedtime.
• The gel label lists a thin layer applied once daily in the evening, in strengths of 0.04%, 0.06%, 0.08%, or 0.1%.
• The gel label says acne may improve after two weeks, but more than seven weeks may be needed for lasting benefit.
• Tretinoin capsules are usually taken twice a day for up to 90 days.

Sources: MedlinePlus (NIH): Tretinoin Topical: MedlinePlus Drug Information ↗ · DailyMed (FDA drug label): DailyMed - RETIN-A MICRO- tretinoin gel ↗ · MedlinePlus (NIH): Tretinoin: MedlinePlus Drug Information ↗

Roughly what it costs

We don't have prices for this yet.

Questions to ask your doctor

• Is Tretinoin a sensible option for me, given my health and the medicines I take?
• Could Tretinoin interact with any medicine or supplement I already take?
• What side effects should I watch for, and when should I stop or call you?
• Would Tretinoin be used for its approved purpose, or off-label for aging?
• How would we tell whether it is helping, and when should we review it?