Lichen Planus: Symptoms, Causes, Diagnosis, and Treatment — A Complete Plain-Language Guide
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Lichen planus is a condition where the immune system attacks skin, mouth, nail, or genital tissue, causing purple itchy bumps, lacy white mouth patches, and nail changes. It is not contagious and often clears on its own within months to years. Most cases are treated with corticosteroid creams, antihistamines, light therapy, or immune-targeting medicines, and a quick, accurate diagnosis matters because other conditions can look similar.
Quick Answer: What is lichen planus?
Lichen planus is an inflammatory condition that most often appears as purple, itchy, flat bumps on the wrists, forearms or ankles, or as lacy white patches in the mouth and genitals. It stems from an irregular immune response and is not contagious. It often clears within months to years, and corticosteroid creams are usually the first treatment. [1]
What the research says
Lichen planus and hepatitis C are linked in both directions. A systematic review and meta-analysis of 192 studies found hepatitis C in 9.42% of people with lichen planus (95% CI 7.27 to 11.58%), about 4-fold more often than in control groups (OR 4.48, 95% CI 3.48 to 5.77) (García-Pola et al., J Clin Med, 2023 [3]).
Oral lichen planus carries a small but real cancer risk. A systematic review and meta-analysis of 101 studies (38,083 patients) found a pooled malignant transformation ratio of 1.43% (95% CI 1.09 to 1.80) for oral lichen planus, rising to 5.13% (95% CI 1.90 to 9.43) when epithelial dysplasia was present (González-Moles and Ramos-García, Cancers, 2024 [4]).
What Is Lichen Planus?
Lichen planus (pronounced LIE-kun PLAY-nus) is a condition that can affect the skin, hair, nails, mouth, and genitals. On the skin, it usually shows up as purple, itchy, flat-topped bumps that develop gradually over several weeks. In the mouth and in the genital mucosa, it forms lacy white patches, sometimes with painful sores [1].
The condition is not contagious. Mild skin cases may not need any treatment at all. If the condition causes pain or intense itching, prescription medicine is often helpful.
Body area affected | Typical appearance |
|---|---|
Skin | Purple, itchy, flat, shiny bumps developing over several weeks |
Mouth (tongue, inner cheeks) | Lacy white patches; sometimes painful sores |
Genital mucosa | Lacy white patches; sometimes painful sores |
Nails | Scarring, loss, dark lines running from nail tip to base |
Hair | Rarely, hair loss |
Ears | Rarely, the ear canal |
How does lichen planus show up on the skin?
The most recognizable form of the condition appears on the skin. The bumps are purple, shiny, and flat. They tend to appear on the inner forearms, wrists, or ankles, and often develop over a period of several weeks rather than appearing suddenly.
When the affected skin is scratched, a distinctive rash can form in lines along the scratches. This happens because trauma to the skin triggers new lesions to appear in that spot.
On the skin: flat, shiny, purple bumps, rash lines along scratches, and dark marks after healing (post-inflammatory hyperpigmentation).
What symptoms does lichen planus cause across the body?
Symptoms vary depending on which part of the body is affected. Nail disease usually involves several nails at once, not just one.
Body area | Symptoms to watch for |
|---|---|
Skin | Purple, shiny, flat bumps; lines of rash along scratches; itchiness |
Mouth | Lacy white patches on the tongue or inside the cheeks; painful sores that may affect eating |
Genitals | Painful sores; lacy white patches; pain during sex in some cases |
Nails | Scarring or loss; dark lines from the nail tip to the base |
Hair | Rarely, hair loss |
Ears | Rarely, ear canal involvement that can lead to hearing loss if untreated |
The mouth symptoms deserve special attention. Oral sores can affect your ability to eat, and the oral form increases the risk of oral cancer. Anyone with mouth patches or sores should get checked promptly.
When should you see a doctor about lichen planus?
See a healthcare provider if tiny bumps or a rash appears on your skin for no known reason, such as contact with poison ivy. Also make an appointment if you notice any symptoms related to the mouth, genitals, scalp, or nails.
Getting a prompt and correct diagnosis matters. A number of other skin and mucous membrane conditions can cause sores and pain, so confirming that the condition is actually lichen planus guides the right treatment.
Signal | What it means |
|---|---|
Unexplained purple, itchy bumps appearing over weeks | Needs diagnosis — not every rash is lichen planus |
Lacy white patches in the mouth | Needs prompt evaluation; oral lichen planus raises oral cancer risk |
Painful genital sores | Needs diagnosis and treatment; genital forms are harder to treat |
Nail changes on several nails | Needs evaluation; nail disease is harder to treat |
Sores affecting eating | Needs prompt care |
What Causes Lichen Planus?
The cause is likely related to the immune system attacking cells of the skin or mucous membranes. Why this irregular immune response happens is not clear. One thing is certain: the condition is not contagious, so you cannot catch it from or pass it to another person [1].
Three known triggers can activate or be associated with the condition.
Potential trigger | How it relates to lichen planus |
|---|---|
Hepatitis C infection | The infection may activate the condition; blood testing is sometimes done |
Pain relievers and other medicines | Certain drugs can activate the immune response |
Metal dental fillings | An allergic reaction to the metal may activate oral disease |
If a doctor believes an infection, allergy, medicine, or other trigger is related to your condition, additional testing or a medicine change may be part of the plan.
Who Is Most at Risk?
Anyone can develop this condition. It most often affects middle-aged adults. When the condition appears in the mouth, it is more likely to affect women than men.
Risk factor | Detail |
|---|---|
Age | Most often affects middle-aged adults |
Sex | Women are more likely than men to get oral lichen planus |
Infections | Hepatitis C can activate the condition |
Medicines | Pain relievers and some other drugs may activate it |
Dental fillings | Allergic reaction to metal fillings may activate oral disease |
What are the possible complications of lichen planus?
Most cases of skin lichen planus clear up on their own, but some forms cause lasting problems.
The condition can be difficult to treat on the vulva and in the vagina. It can cause scarring and severe pain, and sores on the genitals can make sex painful.
The affected skin and nails might stay slightly darker even after healing. This lingering discoloration is cosmetic rather than dangerous.
Oral sores may affect your ability to eat. Importantly, the oral form increases the risk of oral cancer, which is why regular monitoring matters. Rarely, the condition affects the ear canal. Left untreated there, it may lead to hearing loss.
Complication | Area affected | Why it matters |
|---|---|---|
Scarring and severe pain | Vulva and vagina | Hard to treat; may make sex painful |
Dark discoloration after healing | Skin and nails | Cosmetic, usually fades slowly |
Trouble eating | Mouth | Oral sores affect daily life |
Higher oral cancer risk | Mouth | Requires ongoing monitoring |
Hearing loss (if untreated) | Ear canal | Rare but preventable with treatment |
How is lichen planus diagnosed?
Diagnosis starts with the basics. A healthcare provider will talk with you about your symptoms and medical history, then do a physical exam. From there, specific tests confirm the diagnosis [2].
A biopsy is the key test. The provider removes a small piece of affected tissue and sends it to a laboratory. The tissue is examined for the cell patterns that are typical of the condition.
Blood tests may also be ordered to check for health problems related to the condition, such as hepatitis C infection. Testing for hepatitis C matters because the infection can activate the condition and may itself need treatment.
Diagnostic step | What happens | What it tells the doctor |
|---|---|---|
Medical history and physical exam | Provider reviews symptoms, triggers, and examines affected areas | Narrowing down the cause among many conditions that look similar |
Skin biopsy | Small tissue sample removed and examined in a lab | Confirms the cell patterns typical of lichen planus |
Blood tests | Blood drawn for related health problems | Detects hepatitis C and other related conditions |
Diagnosis steps: exam and history, skin biopsy, and blood tests.
What are the treatment options for lichen planus?
Treatment depends heavily on symptoms. If you have no pain or discomfort, you may not need any treatment at all. The skin form often clears up on its own within months to years [2].
Medicines and other treatments can relieve itching, ease pain, and speed healing. More than one approach is often needed to control symptoms. One important caveat: when the disease affects the mucous membranes and nails, it tends to be harder to treat. Even when treatment works, symptoms may return, and follow-up care at least once a year is likely.
Treatment options, from corticosteroid creams to light therapy and home care.
Corticosteroids — the first-line treatment
A prescription corticosteroid cream or ointment is often the first choice for the skin form. It helps ease pain, swelling, and inflammation. If a topical corticosteroid does not help and the condition is severe or widespread, corticosteroid pills or injections may be suggested instead. Side effects vary depending on how the medicine is used, and corticosteroids are safe when used as directed.
Other medicines
Several classes of oral medicines are used when topical treatment is not enough.
Medicine class | Examples | When it is used |
|---|---|---|
Oral anti-infection drugs | Hydroxychloroquine (antimalarial); metronidazole (antibiotic) | Other oral options for lichen planus |
Immune response medicines | Cyclosporine, azathioprine, methotrexate, mycophenolate, sulfasalazine, thalidomide | More severe symptoms; used with some success, further study needed |
Antihistamines | Oral antihistamine | Easing itchy skin |
Retinoids | Acitretin (oral or applied to skin) | Prescribed in some cases; not safe in pregnancy |
Retinoids can cause birth defects, so they are not for people who are pregnant or may become pregnant. With acitretin, pregnancy must also be avoided for at least 3 years after stopping the medicine, and alcohol must be avoided during treatment and for 2 months afterward. If you are pregnant or nursing, your provider may suggest delaying treatment or choosing a different option.
Light therapy
Light therapy, also called phototherapy, may help clear skin lesions. One method exposes the affected skin to ultraviolet B light two to three times a week for several weeks. Be aware of one possible side effect: lasting changes in skin color, known as postinflammatory hyperpigmentation, can occur even after the skin heals.
Treating the trigger
If the condition appears related to an infection, allergy, a medicine, or another trigger, addressing that trigger becomes part of treatment. This may mean switching a medicine or testing for allergens.
Which home care and self-care steps help lichen planus?
Self-care steps can reduce itching and pain caused by the condition. These simple measures work alongside medical treatment.
Self-care step | How to do it |
|---|---|
Lukewarm baths | Add an oatmeal-based bath product, rinse well, pat dry, and apply moisturizer |
Cool compresses | Apply a cool, damp cloth to itchy areas |
Nonprescription hydrocortisone | Use a cream with at least 1% hydrocortisone, only if you are not already using a prescription corticosteroid on the skin |
Avoid scratching | Do not scratch the skin or injure the nails, which can trigger new lesions |
Oral hygiene | Brush twice a day and floss daily if you have oral lichen planus |
Scratching deserves emphasis. Scratching triggers new rashes to form along the scratch lines, creating a cycle of itch, scratch, and more rash. Breaking that cycle with moisturizers, compresses, and antihistamines makes a real difference.
Which alternative medicine options may help lichen planus?
A few small clinical trials have suggested that aloe vera gel may help treat the condition on the vulva, and that aloe vera mouthwash may help with disease of the mouth. The evidence is limited, so discuss these options with your provider.
Stress can worsen symptoms, so approaches that reduce stress may also help. Always talk with your healthcare provider before trying an alternative treatment, because some alternative medicines or supplements have unwanted side effects.
How should you prepare for a lichen planus appointment?
You will likely start by seeing your primary care provider, or you may be referred to a dermatologist who specializes in skin diseases. If the condition affects the vulva or vagina, you may be referred to a gynecologist.
Before your appointment, make a list of your symptoms and how long you have had them, all medicines, vitamins, and supplements you take including doses, and the questions you want to ask.
Prepare | What to bring or note |
|---|---|
Symptom list | Where symptoms appeared, when they started, how long they have lasted |
Medicine list | All medicines, vitamins, and supplements with doses |
Trigger history | New medicines, recent immunizations, known allergies |
Questions | See the lists below |
Questions to ask your provider include: What is the most likely cause of my symptoms? Are there other possible causes? Do I need any tests? How long will these skin changes last? What treatments are available, and which do you recommend? What side effects can I expect? How can I best manage this alongside my other health conditions? Are there restrictions I need to follow? Should I see a specialist? Is there a generic alternative to the medicine you are prescribing? Do you have brochures or recommended websites?
Your provider will likely ask: Where on your body have you noticed symptoms? Are the affected areas itchy or painful? Would you describe the pain as mild, moderate, or severe? Have you recently started new medicines? Have you recently had immunizations? Do you have any allergies?
Conclusion
Lichen planus is a frustrating but usually manageable immune-driven condition. It most often appears as purple, itchy, flat bumps on the wrists, forearms, or ankles, or as lacy white patches in the mouth and genitals. The condition is not contagious, usually strikes middle-aged adults, and frequently clears on its own within months to years. Treatment ranges from simple corticosteroid creams to light therapy and immune-targeting medicines, with self-care steps helping to break the itch-scratch cycle. Because oral lichen planus raises oral cancer risk and genital forms are harder to treat, a prompt, accurate diagnosis is the best first step.
Ready to take the next step? If you have noticed unexplained purple bumps, lacy white mouth patches, or nail changes, book an appointment with your healthcare provider. A quick evaluation, and a biopsy if needed, will confirm what you are dealing with and open the path to relief.
Frequently Asked Questions
What is lichen planus?
Lichen planus is an inflammatory condition of the skin, hair, nails, mouth, and genitals caused by the immune system attacking those tissues. It appears as purple, itchy, flat bumps on skin and lacy white patches in the mouth and genitals.
Is lichen planus contagious?
No. The condition is not contagious. It cannot be passed from person to person through contact of any kind.
What does lichen planus look like on the skin?
Lichen planus appears as purple, shiny, flat, itchy bumps, most often on the inner forearms, wrists, or ankles. The bumps develop over several weeks, and scratching can trigger new rash in lines along the scratches.
What causes lichen planus?
The cause is likely the immune system attacking cells of the skin or mucous membranes, though why this happens is unclear. It may be activated by hepatitis C infection, pain relievers and other medicines, or an allergic reaction to metal in dental fillings.
Who is most likely to get lichen planus?
Anyone can develop it, but it most often affects middle-aged adults. Oral lichen planus is more likely to affect women than men.
Does lichen planus go away on its own?
Often, yes. Skin lesions often clear up on its own within months to years, and mild cases may not need treatment at all.
Is oral lichen planus dangerous?
Oral lichen planus can cause painful sores that affect eating, and it increases the risk of oral cancer. Regular dental checkups and medical monitoring are important.
What is the first treatment for lichen planus?
A prescription corticosteroid cream or ointment is usually the first treatment for the skin form. It eases pain, swelling, and inflammation. Antihistamines can also ease itching.
What happens if lichen planus won't go away?
For severe or widespread cases, options include corticosteroid pills or injections, light therapy, retinoids, antimalarial or antibiotic drugs, and immune response medicines. Mucous membrane and nail forms are harder to treat and may need follow-up at least yearly.
Can light therapy treat lichen planus?
Yes. Phototherapy exposing affected skin to ultraviolet B light two to three times a week for several weeks can help clear skin lesions. One possible side effect is lasting skin color change even after healing.
What home remedies help lichen planus itch?
Lukewarm oatmeal baths, cool damp cloths, at least 1% nonprescription hydrocortisone cream, and avoiding scratching all help. For the oral form, brush twice daily and floss daily.
Further Reading
Related Reading
Lichen Planopilaris: Understanding Scarring Alopecia and Scalp Care explains the form of lichen planus that causes scarring hair loss.
Lichen Nitidus: Understanding Symptoms, Causes, and Skin Care explains a related rash of tiny, shiny skin bumps.
Leukoplakia Symptoms, Causes, and Treatment: What White Mouth Patches Mean explains white mouth patches that can look like oral lichen planus.
Psoriasis: Complete Guide to Symptoms, Types, Causes, and Treatment explains psoriasis, another scaly skin condition often confused with lichen planus.
References
Mayo Clinic Staff. Lichen planus - Symptoms and causes. Mayo Clinic. Accessed October 10, 2026. https://www.mayoclinic.org/diseases-conditions/lichen-planus/symptoms-causes/syc-20351378
Mayo Clinic Staff. Lichen planus - Diagnosis and treatment. Mayo Clinic. Accessed October 10, 2026. https://www.mayoclinic.org/diseases-conditions/lichen-planus/diagnosis-treatment/drc-20351383
García-Pola M, Rodríguez-Fonseca L, Suárez-Fernández C, et al. Bidirectional association between lichen planus and hepatitis C: an update systematic review and meta-analysis. J Clin Med. 2023;12(18):5777. PMID: 37762719. DOI: https://doi.org/10.3390/jcm12185777
González-Moles MÁ, Ramos-García P. An evidence-based update on the potential for malignancy of oral lichen planus and related conditions: a systematic review and meta-analysis. Cancers (Basel). 2024;16(3):608. PMID: 38339358. DOI: https://doi.org/10.3390/cancers16030608
Medical disclaimer
This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. The clinical information in this guide is based on Mayo Clinic patient information accessed in October 2026.
Comments