Alitretinoin: what it treats, how to use it, side effects
Last updated September 7, 2026.
**Alitretinoin is a retinoid, a vitamin A related medicine, sold in the United States as Panretin 0.1% gel for use on the skin.** It binds to retinoid receptors inside skin cells and changes how those cells grow and divide, which shrinks and flattens Kaposi sarcoma lesions over weeks. The most important safety point is pregnancy: retinoids can cause serious birth defects, so you should not use this gel if you are pregnant or planning to become pregnant, and you need reliable contraception while you use it.
What does it treat?
Alitretinoin gel is approved for the cutaneous lesions of AIDS-related Kaposi sarcoma, the purple, red, or brown patches, plaques, and nodules that appear on the skin in people with advanced HIV. It is a local treatment for lesions you can see and reach, not a treatment for the underlying HIV infection and not a treatment for Kaposi sarcoma inside the body. The label says it is not the right choice when systemic therapy is needed, such as more than ten new lesions in the past month, symptomatic swelling from lymph blockage, or Kaposi sarcoma in the lungs or gut. It works alongside antiretroviral therapy, which remains the backbone of care, and it comes as a single ingredient gel with no combination products in the United States. An oral form of alitretinoin, sold as Toctino for severe chronic hand eczema in Canada and parts of Europe, is not approved by the FDA and is not available from US pharmacies.
How do you take it?
Alitretinoin comes as a 0.1% gel in a 60 gram tube. Adults start by applying it twice a day to the Kaposi sarcoma lesions only, then step up to three and then four times a day as the skin tolerates it; four times a day is the ceiling, and there is no benefit to more. Use enough to cover each lesion with a generous coating, keep it off the normal skin around the lesion and away from the eyes, mouth, nose, and genital tissue, and let it dry for 3 to 5 minutes before you put clothing over it. Do not cover the area with a bandage or wrap, and wait at least 3 hours before bathing, showering, or swimming. Food rules do not apply since nothing is swallowed. If you miss an application, put it on when you remember, or skip it if your next one is close, and never double up. Lesions may start to lighten within about 2 weeks, but many people need 8 to 12 weeks or longer, so keep going unless your clinician stops it. Cut back the number of daily applications, or stop for a few days, if the treated skin becomes very red, swollen, or blistered, and call your doctor if the irritation does not settle or the lesions keep spreading.
Side effects to know
- Common: Almost everyone gets some reaction where the gel goes on, most often redness, scaling, dryness, itching, stinging or burning, and mild pain, and this usually starts in the first week or two.
- Serious: Stop applying the gel and get medical advice the same day if the treated skin blisters, weeps, peels in sheets, or becomes severely swollen and painful, which is severe dermatitis and means the frequency was too high for your skin. Also seek urgent care for signs the disease is moving beyond the skin, such as a rapidly swelling arm or leg, new shortness of breath or a cough, or black or bloody stools.
Who should not take it?
Do not use alitretinoin gel if you are pregnant, and do not become pregnant while using it, because retinoids can cause serious birth defects; if you can become pregnant, use effective contraception and tell your clinician right away if a period is late. It is not known whether alitretinoin passes into breast milk, and because of the risk to a nursing infant the label advises stopping breastfeeding before you start the gel. Do not use insect repellents or any other products containing DEET while you are on this gel, since animal studies showed DEET toxicity increased. Keep other creams, ointments, or medicated skin products off the treated lesions unless your clinician approves them, and be careful with medicines that make you sun sensitive, such as tetracyclines, sulfonamides, thiazides, and fluoroquinolones, because the gel can make treated skin burn more easily; stay out of sunlamps and cover treated areas in strong sun. Tell your clinician if you have another inflammatory skin condition on the same areas, and note that safety in children has not been established. Drinking alcohol does not interact with the gel, and there is no known interaction with your HIV medicines, so keep taking antiretroviral therapy exactly as prescribed.
When is it an emergency?
Alitretinoin gel is meant for the skin only. If someone swallows the gel, call Poison Control at 1-800-222-1222 right away, even if they look fine; a large swallowed dose acts like a vitamin A overdose and can cause headache, flushing, nausea and vomiting, dizziness, and severe drowsiness. Call 911 for trouble breathing, swelling of the face, lips, tongue, or throat, widespread hives, fainting, or collapse, which point to a severe allergic reaction. Go to an emergency department for skin that is blistering and breaking open over a large area, for a treated site that becomes hot, spreading, and streaked with fever and chills, which suggests infection, and for sudden shortness of breath, chest pain, coughing up blood, or vomiting blood or passing black stools in someone with Kaposi sarcoma. If gel gets into your eye, rinse with water for 15 minutes and call your clinician or Poison Control.
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Common questions
What is the maximum amount of alitretinoin gel I can use in a day?
Four applications a day is the label ceiling for the 0.1% gel. You start at twice a day and move up to three and then four times a day only as your skin tolerates it, usually with about two weeks at each step. Applying more often than four times a day does not clear lesions faster and mainly causes redness, peeling, and pain. There is no fixed gram limit per day, but the gel goes on the lesions only, not on the healthy skin around them.
Can I drink alcohol while using alitretinoin gel?
Yes. Alitretinoin gel works in the skin and very little reaches the bloodstream, so alcohol does not interact with it. This is different from oral retinoids like isotretinoin and acitretin, where alcohol matters. The gel base does contain alcohol, so let each application dry for 3 to 5 minutes before you dress. If you are drinking heavily enough to miss applications or your HIV medicines, tell your clinician, because consistency matters more than any single dose.
Is alitretinoin safe in pregnancy or while breastfeeding?
No. Alitretinoin is a retinoid and retinoids can cause serious birth defects, so the gel should not be used during pregnancy. If you can become pregnant, use reliable contraception the whole time you are on it and tell your clinician immediately if you think you are pregnant or your period is late. For breastfeeding, it is not known whether the drug passes into human milk, and the label advises stopping nursing before starting the gel because of the potential for serious effects in an infant. Talk with your clinician about other options if you are pregnant, trying to conceive, or nursing.
Do I need to take it with food, or avoid washing the area?
Food rules do not apply, because this gel is used on the skin and not swallowed. Apply it to clean, dry skin, cover the lesion with a generous coating, and let it dry for 3 to 5 minutes before clothing touches it. Wait at least 3 hours after an application before bathing, showering, or swimming so the gel has time to work. Do not put a bandage, wrap, or occlusive dressing over the treated area, and do not layer other creams or ointments on the lesion unless your clinician says to.
What are the signs of an overdose, and what should I do?
Swallowing the gel is the real overdose risk, and it behaves like too much vitamin A: headache, facial flushing, nausea and vomiting, dizziness, and unusual sleepiness. Call Poison Control at 1-800-222-1222 right away if anyone swallows it, and call 911 for trouble breathing, fainting, or collapse. Overuse on the skin does not cause vitamin A poisoning but does cause severe local reactions, with heavy redness, swelling, blistering, and peeling. If that happens, stop applying, and call your clinician about restarting at a lower frequency once the skin heals.
What should I avoid using at the same time as alitretinoin gel?
Avoid all insect repellents and other products containing DEET while you are using the gel, since animal data showed DEET toxicity increased with alitretinoin. Keep other topical products, including medicated creams, ointments, and harsh cleansers, off the treated lesions unless your clinician approves them. Be cautious with medicines that increase sun sensitivity, such as tetracyclines, sulfonamides, thiazide diuretics, and fluoroquinolones, and stay out of sunlamps and strong sun on treated skin. Your HIV medicines are not affected by the gel, so keep taking antiretroviral therapy on schedule and bring your full medicine list to each visit.