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Lichen Planus


Shinjita Das

, MD, Harvard Medical School

Reviewed/Revised Sep 2023
Topic Resources

Lichen planus is a recurrent, pruritic, inflammatory eruption characterized by small, discrete, polygonal, flat-topped, violaceous papules that may coalesce into rough scaly plaques, often accompanied by oral and/or genital lesions. Diagnosis is usually clinical and supported by skin biopsy. Treatment generally requires topical or intralesional corticosteroids. Severe cases may require phototherapy or systemic corticosteroids, retinoids, or immunosuppressants.

Etiology of Lichen Planus

Lichen planus (LP) is thought to be caused by a T cell–mediated autoimmune reaction against basal epithelial keratinocytes in people with genetic predisposition. Medications (especially beta-blockers, nonsteroidal anti-inflammatory drugs [NSAIDs], angiotensin-converting enzyme inhibitors, sulfonylureas, gold, antimalarials, penicillamine, and thiazides) can cause LP; drug-induced LP (sometimes called lichenoid drug eruption) may be indistinguishable from nondrug-induced LP or may have a pattern that is more eczematous.

Symptoms and Signs of Lichen Planus

Typical lesions are pruritic, violaceous (purple), polygonal, flat-topped papules and plaques. Erythema may look more purple or brown on dark skin than on light skin. Lesions initially are 2 to 4 mm in diameter, with angular borders and a distinct sheen in cross-lighting.

They are usually symmetrically distributed, most commonly on the flexor surfaces of the wrists, legs, trunk, glans penis, and oral and vaginal mucosae but can be widespread. The face is rarely involved. Onset may be abrupt or gradual.

Children are affected infrequently.

Skin Manifestations of Lichen Planus

During the acute phase, new papules may appear at sites of minor skin injury (Koebner phenomenon), such as a superficial scratch. Lesions may coalesce or change over time, becoming hyperpigmented, atrophic, hyperkeratotic (hypertrophic lichen planus), or vesiculobullous. Although pruritic, lesions are rarely excoriated or crusted. If the scalp is affected, patchy scarring alopecia (lichen planopilaris) may occur.

The oral mucosa is involved in about 50% of cases; oral lesions may occur without cutaneous lesions. Reticulated, lacy, bluish white, linear lesions (Wickham striae) are a hallmark of oral lichen planus, especially on the buccal mucosae. Tongue margins and gingival mucosae in edentulous areas may also be affected. An erosive form of lichen planus may occur in which the patient develops shallow, often painful, recurrent oral ulcers, which, if long-standing, rarely become cancerous. Chronic exacerbations and remissions are common.

Vulvar and vaginal mucosae are often involved. Up to 50% of women with oral mucosal findings have undiagnosed vulvar lichen planus. In men, genital involvement is common, especially of the glans penis.

Nails are involved in up to 10% of cases. Findings vary in intensity with nail bed discoloration, longitudinal ridging and lateral thinning, and complete loss of the nail matrix and nail, with scarring of the proximal nail fold onto the nail bed (pterygium formation).

Diagnosis of Lichen Planus

  • Clinical evaluation

  • Biopsy

Oral or vaginal lichen planus may resemble leukoplakia Premalignant (dysplastic) changes Growths can originate in any type of tissue in and around the mouth, including connective tissues, bone, muscle, and nerve. Most commonly, growths form on the lips, the sides of the tongue,... read more Premalignant (dysplastic) changes , and the oral lesions must also be distinguished from candidiasis Candidiasis (Mucocutaneous) Candidiasis is skin and mucous membrane infection with Candida species, most commonly Candida albicans. Infections can occur anywhere and are most common in skinfolds, digital... read more Candidiasis (Mucocutaneous) , carcinoma Overview of Skin Cancer Skin cancer is the most common type of cancer and commonly develops in sun-exposed areas of skin. Skin cancers can be found on any location of the body but are most commonly diagnosed on the... read more , aphthous ulcers Recurrent Aphthous Stomatitis Recurrent aphthous stomatitis (RAS) is a common condition in which round or ovoid painful ulcers recur on the oral mucosa. Etiology is unclear. Diagnosis is clinical. Treatment is symptomatic... read more Recurrent Aphthous Stomatitis , pemphigus, mucous membrane (cicatricial) pemphigoid Mucous Membrane Pemphigoid Mucous membrane pemphigoid is the designation given to a heterogeneous group of rare chronic autoimmune disorders that tend to cause waxing and waning bullous lesions of the mucous membranes... read more , and chronic erythema multiforme Erythema Multiforme Erythema multiforme is an inflammatory reaction, characterized by target or iris skin lesions. Oral mucosa may be involved. Diagnosis is clinical. Lesions spontaneously resolve but frequently... read more Erythema Multiforme .

Typically, biopsy is done.

If lichen planus is diagnosed, laboratory testing for liver dysfunction, including hepatitis B and C infections, should be considered.

Treatment of Lichen Planus

  • Local treatments

  • Systemic treatments

  • Sometimes light therapy

Asymptomatic lichen planus does not require treatment. Medications suspected of triggering lichen planus should be stopped; it can takes weeks to months after the offending medication has been stopped for the lesions to resolve.

Local treatments

Few controlled studies have evaluated treatments. Options differ by location and extent of disease.

Most cases of lichen planus on the trunk or extremities can be treated with topical treatments. Topical corticosteroids are first-line treatment for most cases of localized disease. High-potency ointments or creams (eg, clobetasol, fluocinonide) may be used on the thicker lesions on the extremities; lower-potency corticosteroids (eg, hydrocortisone, desonide) may be used on the face, groin, and axillae. As always, courses should be limited to reduce risk of corticosteroid atrophy. Potency may be enhanced with use of polyethylene wrapping or flurandrenolide tape.

Intralesional corticosteroids (triamcinolone acetonide solution diluted with saline to 5 to 10 mg/mL) can be used every 4 weeks for hyperkeratotic plaques, scalp lesions, and lesions resistant to other therapies.

Systemic treatments and phototherapy

Local therapy is impractical for generalized lichen planus; thus, an oral medication or phototherapy is used. Oral corticosteroids (eg, prednisone 20 mg once a day for 2 to 6 weeks followed by a taper) may be used for severe cases. The disease may rebound when therapy ceases; however, long-term systemic corticosteroids should not be used.

Oral retinoids (eg, acitretin) are indicated for otherwise recalcitrant cases. Light therapy using psoralen plus ultraviolet A (PUVA) or narrowband ultraviolet B (NBUVB) is an alternative to oral therapies, especially if they have failed or are contraindicated.

Based on case reports and case series, other systemic options may include griseofulvin, cyclosporine, dapsone, hydroxychloroquine, and azathioprine. Observational data also support the use of apremilast (a phosphodiesterase-4 inhibitor used to treat psoriasis) (1 Treatment references Lichen planus is a recurrent, pruritic, inflammatory eruption characterized by small, discrete, polygonal, flat-topped, violaceous papules that may coalesce into rough scaly plaques, often accompanied... read more Treatment references ).

There are also reports of favorable outcomes with off-label use of IL-17, IL-23, and tumor necrosis factor (TNF) inhibitors in the management of lichen planus (2 Treatment references Lichen planus is a recurrent, pruritic, inflammatory eruption characterized by small, discrete, polygonal, flat-topped, violaceous papules that may coalesce into rough scaly plaques, often accompanied... read more Treatment references ).

Oral lichen planus

Treatment of oral lichen planus differs slightly from the treatment of other affected areas. Viscous lidocaine may help relieve symptoms of erosive ulcers; because inflamed mucous membranes can absorb high amounts, dose should not exceed 200 mg (eg, 10 mL of a 2% solution) or 4 mg/kg (in children) 4 times a day. Tacrolimus 0.1% ointment applied twice daily may induce lasting remission, but the data are limited.

Other treatment options include topical (in an adhesive base), intralesional, and systemic corticosteroids.

Erosive oral lichen planus may respond to oral dapsone, hydroxychloroquine, or cyclosporine. Cyclosporine rinses also may be helpful.

Treatment references

  • 1. Viswanath V, Joshi P, Dhakne M, et al: Evaluation of the efficacy and safety of apremilast in the management of lichen planus. Clin Cosmet Investig Dermatol 15:2593-2600, 2022. doi: 10.2147/CCID.S390591

  • 2. Mital R, Gray A, Minta A, et al: Novel and off-label biologic use in the management of hidradenitis suppurativa, pyoderma gangrenosum, lichen planus, and seborrheic dermatitis: A narrative review. Dermatol Ther (Heidelb) 13(1):77–94, 2023. doi: 10.1007/s13555-022-00860-5

Prognosis for Lichen Planus

Many cases resolve without intervention, presumably because the inciting agent is no longer present. Recurrence after years may be due to reexposure to the trigger or some change in the triggering mechanism.

Vulvovaginal lichen planus may be chronic and refractory to therapy, causing decreased quality of life and vaginal or vulvar scarring.

Oral mucosal lesions usually persist for life.

Key Points

  • Lichen planus (LP) is thought to be an autoimmune disorder in patients with a genetic predisposition but may be caused by medications or be associated with disorders such as hepatitis C.

  • LP is characterized by recurrent, pruritic papules that are polygonal, flat-topped, and violaceous and can coalesce into plaques.

  • Oral and genital lesions can develop, become chronic, and cause morbidity.

  • Diagnose LP by clinical appearance and, if necessary, biopsy.

  • Treat localized LP with topical or injected corticosteroids.

  • Treat generalized LP with oral medications or phototherapy.

Drugs Mentioned In This Article

Drug Name Select Trade
Cuprimine, Depen, D-PENAMINE
Engerix-B, Engerix-B Pediatric, H-B-Vax, HEPLISAV-B, PreHevbrio, RDNA H-B Vax II, Recombivax HB, Recombivax HB Pediatric/Adolescent
Clobetavix, Clobevate, Clobex, Clodan, Cormax, Embeline, Embeline E, Impeklo, Impoyz, Olux, Olux-E, Olux-Olux-E Complete Pack, Temovate, Temovate E, Temovate Scalp, Tovet
Fluovix, Fluovix Plus, Lidex, Lidex -E, Vanos
A-Hydrocort, Ala-Cort, Ala-Scalp, Alkindi, Anucort-HC, Anumed-HC, Anusol HC, Aquaphor Children's Itch Relief, Aquaphor Itch Relief, Balneol for Her, Caldecort , Cetacort, Colocort , Cortaid, Cortaid Advanced, Cortaid Intensive Therapy, Cortaid Sensitive Skin, CortAlo, Cortef, Cortenema, Corticaine, Corticool, Cortifoam, Cortizone-10, Cortizone-10 Cooling Relief, Cortizone-10 External Itch Relief, Cortizone-10 Intensive Healing, Cortizone-10 Plus, Cortizone-10 Quick Shot, Cortizone-5 , Dermarest Dricort, Dermarest Eczema, Dermarest Itch Relief, Encort, First - Hydrocortisone, Gly-Cort , GRx HiCort, Hemmorex-HC, Hemorrhoidal-HC, Hemril , Hycort, Hydro Skin, Hydrocortisone in Absorbase, Hydrocortone, Hydroskin , Hydroxym, Hytone, Instacort, Lacticare HC, Locoid, Locoid Lipocream, MiCort-HC , Monistat Complete Care Instant Itch Relief Cream, Neosporin Eczema, NuCort , Nutracort, NuZon, Pandel, Penecort, Preparation H Hydrocortisone, Proctocort, Proctocream-HC, Procto-Kit, Procto-Med HC , Procto-Pak, Proctosert HC , Proctosol-HC, Proctozone-HC, Rectacort HC, Rectasol-HC, Rederm, Sarnol-HC, Scalacort, Scalpicin Anti-Itch, Solu-Cortef, Texacort, Tucks HC, Vagisil Anti-Itch, Walgreens Intensive Healing, Westcort
Desonate, DesOwen, LoKara, Tridesilon, Verdeso
Cordran, Cordran SP, Cordran Tape, Nolix
Aristocort, Aristocort A, Aristocort Forte, Aristocort HP, Aristo-Pak, Aristospan, Azmacort, Children's Nasacort Allergy 24HR Nasal Spray, Cinalog, Cinolar, Flutex, Hexatrione, Kenalog, Kenalog in Orabase, Kenalog-10, Kenalog-40, Kenalog-80, Nasacort, Nasacort AQ, Oralone, SP Rx 228 , Tac-3 , Triacet , Triamonide , Trianex , Triderm , Triesence, XIPERE, Zilretta
Deltasone, Predone, RAYOS, Sterapred, Sterapred DS
Fulvicin P/G, Fulvicin U/F, Grifulvin V, Grisactin, Gris-Peg
Cequa, Gengraf , Neoral, Restasis, Sandimmune, SangCya, Verkazia, Vevye
Plaquenil, Quineprox
Azasan, Imuran
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, AsperFlex, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidocan III, DermacinRx Lidogel, DermacinRx Lidorex, DERMALID, Dologesic, Ela-Max, GEN7T, Glydo, Gold Bond, LidaFlex, LidaMantle, Lido King Maximum Strength, Lidocan, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , LidoLite, Lidomar , Lidomark, LidoPure, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lubricaine For Her, Lydexa, Moxicaine, Numbonex, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Salonpas Lidocaine, Senatec, Solarcaine, SUN BURNT PLUS, Tranzarel, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, Zingo, Zionodi, ZTlido
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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