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ENGLISH
MERCK MANUAL
Consumer Version
HEALTH TOPICS
HEALTHY LIVING
SYMPTOMS
EMERGENCIES
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COMMENTARY
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HEALTH TOPICS
HEALTHY LIVING
SYMPTOMS
EMERGENCIES
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Skin Disorders
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Skin Disorders
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Biology of the Skin
Structure and Function of the Skin
Layers of the Skin
Epidermis
Dermis
Fat layer
Descriptions of Skin Marks, Growths, and Color Changes
Types of Skin Marks and Growths
Color Changes in the Skin
Diagnosis of Skin Disorders
Biopsy
Scrapings
Culture
Wood Light (Black Light)
Tzanck Testing
Diascopy
Skin Tests
Effects of Aging on the Skin
Treatment of Skin Disorders
Treatment of Skin Disorders
Topical Preparations
Types of Topical Medications
Cleansing agents
Protective agents
Moisturizing agents (emollients)
Drying agents
Anti-itch agents
Anti-inflammatory agents
Anti-infective agents
Keratolytics
Dressings
Nonocclusive dressings
Occlusive dressings
Acne and Related Disorders
Acne
Causes
Symptoms
Diagnosis
Treatment
Mild acne
Moderate acne
Severe acne
Cystic acne
Acne scars
Prognosis
Hidradenitis Suppurativa
Diagnosis
Treatment
Perioral Dermatitis
Diagnosis
Treatment
Rosacea
Symptoms
Diagnosis
Treatment
Bacterial Skin Infections
Overview of Bacterial Skin Infections
Classification
Causes
Risk Factors
Treatment
Prevention
Cellulitis
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Erysipelas
Symptoms
Diagnosis
Treatment
Erythrasma
Diagnosis
Treatment
Folliculitis and Skin Abscesses
Folliculitis
Skin Abscesses
Impetigo and Ecthyma
Symptoms
Diagnosis
Treatment
Lymphadenitis
Symptoms
Diagnosis
Treatment
Lymphangitis
Symptoms
Diagnosis
Treatment
Necrotizing Skin Infections
Symptoms
Diagnosis
Treatment
Prognosis
Staphylococcal Scalded Skin Syndrome
Symptoms
Diagnosis
Treatment
Prognosis
Blistering Diseases
Overview of Blistering Disorders
More Information
Bullous Pemphigoid
Symptoms
Diagnosis
Treatment
Prognosis
More Information
Dermatitis Herpetiformis
Symptoms
Diagnosis
Treatment
More Information
Mucous Membrane Pemphigoid
Causes
Symptoms
Diagnosis
Treatment
Prognosis
More Information
Pemphigus Vulgaris
Symptoms
Diagnosis
Treatment
Prognosis
More Information
Cornification Disorders
Corns and Calluses
Symptoms
Diagnosis
Treatment
Ichthyosis
Inherited ichthyoses
Acquired ichthyoses
Diagnosis
Treatment
Keratosis Pilaris
Symptoms
Diagnosis
Treatment
Dry Skin (Xeroderma)
Diagnosis
Treatment
Fungal Skin Infections
Overview of Fungal Skin Infections
Diagnosis
Treatment
Candidiasis (Yeast Infection)
Symptoms
Cutaneous candidiasis
Vaginal candidiasis and penile candidiasis
Thrush
Angular cheilitis (perlèche)
Nail candidiasis
Chronic mucocutaneous candidiasis
Diagnosis
Treatment
Dermatophytid Reaction
Diagnosis
Treatment
Intertrigo
Diagnosis
Treatment
Tinea Versicolor
Symptoms
Diagnosis
Treatment
Prognosis
Overview of Dermatophytoses (Ringworm, Tinea)
Symptoms
Diagnosis
Treatment
Athlete's Foot (Tinea Pedis)
Symptoms
Diagnosis
Treatment
Beard Ringworm (Tinea Barbae)
Diagnosis
Treatment
Body Ringworm (Tinea Corporis)
Diagnosis
Treatment
Jock Itch (Tinea Cruris)
Diagnosis
Treatment
Scalp Ringworm (Tinea Capitis)
Symptoms
Kerion
Diagnosis
Treatment
Hair Disorders
Overview of Hair Growth
Alopecia (Hair Loss)
Causes
Androgenetic alopecia
Alopecia areata
Central centrifugal cicatricial alopecia
Cutaneous lupus erythematosus
Hormone imbalance
Medications
Nutritional disorders
Physical stresses
Psychological stress
Ringworm of the scalp (tinea capitis)
Traction alopecia
Evaluation
Warning signs
When to see the doctor
What the doctor does
Testing
Treatment
Medications
Hair transplantation
Wigs
Other options
Key Points
More Information
Alopecia Areata
Symptoms
Diagnosis
Treatment
More Information
Hairiness
Causes
Hirsutism
Hypertrichosis
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Physical methods
Hormone therapy
Other methods
Key Points
Ingrown Beard Hairs
Treatment
Prevention
Hypersensitivity and Reactive Skin Disorders
Overview of Hypersensitivity and Reactive Skin Disorders
Diagnosis
Treatment
Drug Rashes
Allergic drug rashes
Nonallergic drug rashes
Symptoms
Diagnosis
Treatment
Erythema Multiforme
Symptoms
Diagnosis
Treatment
Erythema Nodosum
Symptoms
Diagnosis
Treatment
Granuloma Annulare
Symptoms
Diagnosis
Treatment
Panniculitis
Symptoms
Diagnosis
Treatment
Pyoderma Gangrenosum
Symptoms
Diagnosis
Treatment
Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN)
Symptoms
Diagnosis
Treatment
Prognosis
Itching and Dermatitis
Itching
Causes
Skin disorders
Systemic (bodywide) disorders
Disorders of the nervous system
Mental health conditions
Drugs, medications, and chemicals
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Skin care
Topical treatments
Systemic treatments
Key Points
Hives
Angioedema
Causes
Acute hives
Chronic hives
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Medications
Essentials for Older Adults: Hives
Key Points
Overview of Dermatitis
Symptoms
Diagnosis
Treatment
Prevention
Atopic Dermatitis (Eczema)
Symptoms
Complications of atopic dermatitis
Diagnosis
Treatment
General care and itch relief
Corticosteroids
Other treatments
Prognosis
Prevention
Contact Dermatitis
Irritant contact dermatitis
Allergic contact dermatitis
Symptoms
Diagnosis
Treatment
Prognosis
Prevention
Erythroderma
Symptoms
Diagnosis
Treatment
Prognosis
Hand and Foot Dermatitis
Symptoms
Diagnosis
Treatment
Lichen Simplex Chronicus
Symptoms
Diagnosis
Treatment
Nummular Dermatitis
Symptoms
Diagnosis
Treatment
Poison Ivy
Symptoms
Diagnosis
Treatment
Prevention
More Information
Seborrheic Dermatitis
Symptoms
Diagnosis
Treatment
Adults and older children
Infants and young children
Stasis Dermatitis
Symptoms
Diagnosis
Treatment
Treatment of chronic venous insufficiency
Treatment of dermatitis
Treatment of ulcers
Nail Disorders
Overview of Nail Disorders
Causes
Deformities, Dystrophies, and Discoloration of the Nails
Birth deformities of the nail
Nail deformities and dystrophies associated with systemic diseases
Deformities and dystrophies associated with skin diseases
Effect of drugs on nails
Median nail dystrophy
Melanonychia striata
Onycholysis
Pincer nail deformity
Fingernail and Toenail Injury
Activity-related toenail injury
Nail-biting
Onychogryphosis
Onychotillomania
Subungual hematoma
White spots
Green Nail Syndrome
Ingrown Toenail
Onychomycosis
Causes
Symptoms
Diagnosis
Treatment
Oral antifungal drugs
Topical treatments
Foot care
Acute Paronychia
Treatment
Chronic Paronychia
Treatment
Retronychia
Treatment
Tumors of the Nails
Verruca Vulgaris
Noncancerous Skin Growths
Overview of Skin Growths
Causes
Diagnosis
Treatment
Cutaneous Cysts
Dermatofibromas
Keloids
Lipomas
Moles
Diagnosis
Treatment
Atypical moles
Symptoms
Diagnosis
Prevention
Treatment
More Information
Seborrheic Keratoses
Skin Tags
Overview of Growths and Malformations of the Vessels
Hemangiomas
Hemangiomas of infancy (also called strawberry or infantile hemangiomas)
Cherry angiomas
Lymphangiomas
Port-Wine Stains
Pyogenic Granulomas
Spider Angiomas
Parasitic Skin Infections
Bedbug Infestation
Symptoms
Diagnosis
Treatment
Prevention
Cutaneous Larva Migrans
Diagnosis
Treatment
Cutaneous Myiasis
Furuncular myiasis
Wound myiasis
Migratory myiasis
Delusional Parasitosis
Diagnosis
Treatment
Lice Infestation
Head lice
Body lice
Pubic lice
Symptoms
Diagnosis
Treatment
Head lice treatment
Pubic lice treatment
Body lice treatment
Scabies Infestation
Symptoms
Diagnosis
Treatment
Pigment Disorders
Overview of Skin Pigment
Pigment disorders
Albinism
Symptoms
Diagnosis
Treatment
Hyperpigmentation
Localized Hyperpigmentation
Lentigines
Widespread Hyperpigmentation
Hyperpigmentation caused by medications and heavy metals
Melasma
Symptoms
Diagnosis
Treatment
Vitiligo
Causes
Symptoms
Diagnosis
Treatment
Topical therapy
Phototherapy
Oral therapy
Surgery
Bleaching
Pressure Sores
Pressure Sores
Risk Factors
Causes
Pressure
Traction
Friction
Moisture
Symptoms
Complications
Diagnosis
Treatment
Pressure relief
Wound cleaning and dressing
Pain management
Infection control
Nutrition
Surgery
Prognosis
Prevention
Psoriasis and Scaling Disorders
Introduction to Psoriasis and Scaling Diseases
Psoriasis
Symptoms
Flare-ups
Uncommon types of psoriasis
Diagnosis
Treatment
Topical treatments
Phototherapy
Systemic treatments
More Information
Lichen Planus
Symptoms
Diagnosis
Treatment
Lichen planus on the skin
Lichen planus in the mouth
Prognosis
Lichen Sclerosus
Symptoms
Diagnosis
Treatment
Parapsoriasis
Symptoms
Diagnosis
Treatment
Prognosis
Pityriasis Rosea
Symptoms
Diagnosis
Treatment
Prognosis
Pityriasis Rubra Pilaris
Symptoms
Diagnosis
Treatment
Skin Cancers
Overview of Skin Cancer
Treatment
Prevention
Screening for skin cancer
More Information
Basal Cell Carcinoma
Symptoms
Diagnosis
Treatment
Prognosis
Prevention
More Information
Squamous Cell Carcinoma
Symptoms
Diagnosis
Treatment
Prognosis
Prevention
More Information
Squamous Cell Carcinoma in Situ
Diagnosis
Treatment
Prevention
More Information
Keratoacanthomas
Diagnosis
Treatment
Prevention
More Information
Atypical Fibroxanthoma
Diagnosis
Treatment
Prevention
Melanoma
Risk Factors
Symptoms
Diagnosis
Treatment
Melanoma that has spread
Prognosis
Prevention
More Information
Merkel Cell Carcinoma
Symptoms
Diagnosis
Treatment
Prevention
More Information
Kaposi Sarcoma
Symptoms
Classic Kaposi sarcoma
AIDS-associated Kaposi sarcoma
Iatrogenic Kaposi sarcoma (immunosuppressive Kaposi sarcoma)
Endemic Kaposi sarcoma
Non-epidemic Kaposi sarcoma
Diagnosis
Treatment
Classic Kaposi sarcoma
Iatrogenic Kaposi sarcoma
AIDS-associated Kaposi sarcoma
Endemic Kaposi sarcoma
Non-epidemic Kaposi sarcoma
More Information
Paget Disease of the Breast
Symptoms
Diagnosis
Treatment
More Information
Sunlight and Skin Damage
Overview of Sunlight and Skin Damage
Ultraviolet light
Natural protection
Photoaging
Actinic keratoses
Skin cancers
Treatment
Photoaging
Actinic keratoses
Skin cancers
Actinic Keratoses
Symptoms
Diagnosis
Treatment
Photosensitivity Reactions
Solar urticaria
Chemical photosensitivity
Polymorphous light eruption
Diagnosis
Treatment
Prevention
Sunburn
Treatment
Prevention
Avoidance
Clothing
Sunscreens
Supplements
Sweating Disorders
Introduction to Sweating Disorders
Body Odor
Treatment
Diminished Sweating
Diagnosis
Treatment
Excessive Sweating
Focal excessive sweating
Generalized excessive sweating
Symptoms
Diagnosis
Treatment
Aluminum chloride solution
Anticholinergic medications
Clonidine
Botulinum toxin type A
Medical devices
Surgery
Prickly Heat
Diagnosis
Treatment
Viral Skin Infections
Molluscum Contagiosum
Symptoms
Diagnosis
Treatment
Warts
Symptoms
Common warts
Plantar warts and palmar warts
Mosaic warts
Periungual warts
Filiform warts
Flat warts
Genital warts
Diagnosis
Treatment
Chemicals
Freezing (cryotherapy)
Burning (electrosurgery) and cutting
Other therapies
Prevention
