lichen planus

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Lichen Planus



Lichen planus is a skin condition of unknown origin that produces small, shiny, flat-topped, itchy pink or purple raised spots on the wrists, forearms or lower legs, especially in middle-aged patients.


Lichen planus affects between 1-2% of the population, most of whom are middle-aged women. The condition is less common in the very young and the very old. The lesions are found on the skin, genitals, and in the mouth. Most cases resolve spontaneously within two years. Lichen planus is found throughout the world and is equally distributed among races.

Causes and symptoms

No one knows what causes lichen planus, although some experts suspect that it is an abnormal immune reaction following a viral infection, probably aggravated by stress. The condition is similar to symptoms caused by exposure to arsenic, bismuth, gold, or developers used in color photography. Occasionally, lichen planus in the mouth appears to be an allergic reaction to medications, filling material, dental hygiene products, chewing gum or candy.
Symptoms can appear suddenly, or they may gradually develop, usually on the arms or legs. The lesions on the skin may be preceded by a dryness and metallic taste or burning in the mouth.
Once the lesions appear, they change over time into flat, glistening, purple lesions marked with white lines or spots. Mild to severe itching is common. White, lacy lesions are usually painless, but eroded lesions often burn and can be painful. As the lesions clear up, they usually leave a brown discoloration behind, especially in dark skinned people.
Lichen planus in the mouth occurs in six different forms with a variety of symptoms, appearing as lacy-white streaks, white plaques, or eroded ulcers. Often the gums are affected, so that the surface of the gum peels off, leaving the gums red and raw.


A doctor can probably diagnose the condition simply from looking at the characteristic lesions, but a skin biopsy may be needed to confirm the diagnosis.


Treatment is aimed at easing symptoms. Itching can be treated with steroid creams and oral antihistamines. Severe lesions can be treated with corticosteroids by mouth, or combinations of photochemotherapy (PUVA) and griseofulvin.
Patients with lesions in the mouth may find that regular professional cleaning of the teeth and conscientious dental care improve the condition. Using milder toothpastes instead of tartar control products also seems to lessen the number of ulcers and makes them less sensitive.


While lichen planus can be annoying, it is usually fairly benign and clears up on its own. It may take months to reach its peak, but it usually clears up within 18 months.

Key terms

PUVA — A type of phototherapy that combines the oral or topical photosensitizing chemical psoralen, plus long-wave ultraviolet light-A (UVA).



Lichen Planus Self-Help. Baylor College of Dentistry.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


1. any of certain plants formed by the mutualistic combination of an alga and a fungus.
2. any of various papular skin diseases in which the lesions are typically small, firm papules set very close together.
lichen amyloido´sus a condition characterized by localized cutaneous amyloidosis.
lichen fibromucinoido´sus (lichen myxedemato´sus) a condition resembling myxedema but unassociated with hypothyroidism, marked by mucinosis and a widespread eruption of asymptomatic, soft, pale red or yellowish, discrete papules.
lichen ni´tidus a usually asymptomatic chronic inflammatory eruption consisting of numerous glistening, flat-topped, discrete, smooth, commonly skin-colored micropapules, located most often on the penis, lower abdomen, inner thighs, flexor aspects of the wrists and forearms, breasts, and buttocks. Widespread involvement may produce confluence of the lesions, with formation of scaly plaques.
lichen pila´ris lichen spinulosus.
lichen planopila´ris a variant of lichen planus characterized by formation of cone-shaped horny papules around the hair follicles, in addition to the typical lesions of ordinary lichen planus.
lichen pla´nus an inflammatory skin disease with wide, flat, purplish, shiny papules in circumscribed patches; it may involve the hair follicles, nails, and buccal mucosa; called also lichen ruber planus.
lichen ru´ber monilifor´mis a generalized or localized eruption with either round, dome-shaped, waxy, dark or bright red papules, or waxy, yellow, milia-like papules, often forming a moniliform (string-of-beads) pattern, sometimes arranged in keloidal bands. Some authorities consider the condition to be a variant of lichen simplex chronicus.
lichen ru´ber pla´nus lichen planus.
lichen sclero´sus (lichen sclero´sus et atro´phicus) a chronic atrophic skin disease marked by white papules with an erythematous halo and keratotic plugging. It sometimes affects the vulva (kraurosis vulvae) or penis (balanitis xerotica obliterans).
lichen scrofuloso´rum (lichen scrofulo´sus) a form of tuberculid manifested as an eruption of clusters of lichenoid papules on the trunk of children with tuberculous disease.
lichen sim´plex chro´nicus dermatosis of psychogenic origin, marked by a pruritic discrete, or more often, confluent lichenoid papular eruption, usually confined to a localized area. Mechanical trauma, such as scratching or rubbing the area, is a factor in its development. The lesions may arise from normal skin or they may occur as a complication of other forms of dermatitis. Called also circumscribed or localized neurodermatitis and lichen chronicum simplex.

Treatment consists of administration of corticosteroids applied locally as a cream or given by intralesional injection to relieve the pruritus. The area should be protected by light dressings and the patient encouraged to avoid mental stress, emotional upsets, and irritation of the affected area. The application of very hot or very cold compresses may afford temporary relief of the itching. The condition tends to become chronic with unexplained remissions and reappearance of lesions in a different part of the body.
lichen spinulo´sus a condition in which there is a horn or spine in the center of each hair follicle; called also lichen pilaris.
lichen stria´tus a self-limited condition characterized by a linear lichenoid eruption, usually in children.
lichen urtica´tus papular urticaria.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

li·chen pla·'nus

eruption of flat-topped, shiny, violaceous papules on flexor surfaces, male genitalia, and buccal mucosa of unknown cause; may form linear groups; microscopically characterized by a bandlike subepidermal lymphocytic infiltrate. Spontaneous resolution is common after months to years.
Farlex Partner Medical Dictionary © Farlex 2012

lichen planus

A pruritic dermopathy of flexor surfaces (especially wrist), orogenital mucosa, hands, feet, lower back, and the pretibial area, which is characterised by papular thickening of upper dermis, and a shiny violaceous surface.
Lichenoid drug reaction, lichenoid keratosis, granuloma annulare, systemic lupus eythematosus, psoriasis.

Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

lichen planus

Dermatology A pruritic dermatopathy of flexor surfaces–especially wrist, orogenital mucosa, characterized by papular thickening of upper dermis, a shiny violaceous surface Management Corticosteroids
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

li·chen pla·nus

, lichen ruber planus (lī'ken plā'nŭs, rū'bĕr)
Eruption of flat-topped, shiny, violaceous papules on flexor surfaces, male genitalia, and buccal mucosa of unknown cause; may form linear groups. Spontaneous resolution is common after months to years.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
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lichen planus

An inflammatory rash marked by the presence of itchy, red to violet, polygon-shaped papules, which typically appear on the scalp, in the oral cavity, or on the limbs. The papules may merge into plaques crisscrossed by Wickham striae. Typically, the rash persists for 1 to 2 years and then spontaneously improves although about one in five patients will suffer a recurrence. Synonym: lichen ruber planus See: illustration


The cause of the rash is unknown, but it is occasionally associated with the use of chemicals (such as photoprocessing compounds, gold) or medications (such as beta blockers, diuretics, nonsteroidal anti-inflammatory drugs).


Corticosteroids, applied topically, taken orally, or injected into the lesions, are often effective.

See also: lichen
Medical Dictionary, © 2009 Farlex and Partners

lichen planus

An uncommon skin disease featuring small, intensely itchy, slightly raised, reddish-purple patches that enlarge and run together to form flat-topped plaques up to 2 cm in diameter. They are usually found on the fronts of the wrists and forearms, the sides of the calves and ankles and the lower back. The cause is unknown. Lichen planus usually clears up within 2 years. Itching can be relieved by hydrocortisone ointment.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


Sir William J.E., English dermatologist, 1809-1884.
Wilson lichen - eruption of flat-topped, shiny, violaceous papules on flexor surfaces, male genitalia, and buccal mucosa of unknown cause. Synonym(s): lichen planus
Medical Eponyms © Farlex 2012

li·chen pla·nus

, lichen ruber planus (lī'ken plā'nŭs, rū'bĕr)
Eruption of flat-topped violaceous papules on flexor surfaces and buccal mucosa of unknown cause.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Based on data available, the present study is the first study on the use of a natural product (propolis) with the aim of decreasing IL-17 serum levels in patients with ulcerative oral lichen planus, given the etiopathogenesis of the disease, i.e.
Among the various cases, the clinical morphology made us to think about lichen planus. On further examinations, flat polygonal hyperpigmented papules of <0.5 cm size were found over both upper and lower extremities.
Ziyad Khamaysi described the results of a retrospective study of 15 women and 6 men with erosive, recalcitrant oral lichen planus, treated with hydroxychloroquine.
Hypertrophic lichen planus versus prurigo nodularis: a dermoscopic perspective.
Keywords: Diabetes, impaired glucose metabolism, lichen planus.
These six classes of erythemato-squamous diseases include pityriasis rubra pilaris, seborrheic dermatitis, psoriasis, lichen planus, chronic dermatitis, and pityriasis rosea.
Differential diagnosis of lupus erythematosus on the lips may include allergic contact dermatitis, actinic cheilitis, lichen planus, psoriasis, erythema multiforme, pemphigus vulgaris, squamous cell carcinoma, etc.
The oral mucosa adjacent to the lesion demonstrated histopathological features consistent with lichen planus. Specifically, the epithelial hyperplastic pattern in a transitional manner changed into a relatively thinner squamous epithelium that exhibited parakeratosis, basal cell hydropic degeneration, and a band-like subepithelial dense chronic inflammatory infiltrate mainly by lymphocytes (Figure 2, inset).
Inflammatory linear verrucous epidermal nevus Linear epidermal nevus Linear psoriasis Linear lichen planus Linear verruca plana Linear porokeratosis Linear Darier's disease Blaschkitis
We identified a great number of markers of oral lichen planus malignant transformation and classified them into the following categories: apoptosis-related biomarkers, cell cycle regulators, tissue remodeling factors, inflammation-related factors, galectins, and intercellular adhesion proteins.
Histopathological examination of the lesions showed lichen planus in the right and left buccal mucosae (Figure 2(a)) and oral squamous cell carcinoma (OSCC) in the left buccal mucosa (Figure 2(b)).
Lichen planus is a chronic mucocutaneous T cell mediated disease that usually involves the oral mucosa [1].