Health Topics

Skin hair and nails

Skin Conditions
National Library of Medicine
Cutaneous Disorders
Dermatology
Dermatologic disorders

Your skin is your body's largest organ. It covers and protects your body. Your skin

  • Holds body fluids in, preventing dehydration
  • Keeps harmful microbes out, preventing infections
  • Helps you feel things like heat, cold, and pain
  • Keeps your body temperature even
  • Makes vitamin D when the sun shines on it

Anything that irritates, clogs, or inflames your skin can cause symptoms such as redness, swelling, burning, and itching. Allergies, irritants, your genetic makeup, and certain diseases and immune system problems can cause rashes, hives, and other skin conditions. Many skin problems, such as acne, also affect your appearance.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases


Skin Diseases
Skin, Hair and Nails
Your skin is your body's largest organ. It covers and protects your body. Your skin Holds body fluids in, preventing dehydration Keeps harmful microbes out, ...
Anatomy
National Library of Medicine

Anatomy is the science that studies the structure of the body. On this page, you'll find links to descriptions and pictures of the human body's parts and organ systems from head to toe.


Anatomy
Digestive System
Blood, Heart and Circulation
Eyes and Vision
Bones, Joints and Muscles
Kidneys and Urinary System
Brain and Nerves
Lungs and Breathing
Ear, Nose and Throat
Mouth and Teeth
Skin, Hair and Nails
Pregnancy and Reproduction
Immune System
Endocrine System
Male Reproductive System
Anatomy is the science that studies the structure of the body. On this page, you'll find links to descriptions and pictures of the human body's parts and organ ...
Nail Diseases
National Library of Medicine
Fingernails
Ingrown Nail
Onychomycosis
Paronychia
Toenails

Your toenails and fingernails protect the tissues of your toes and fingers. They are made up of layers of a hardened protein called keratin, which is also in your hair and skin. The health of your nails can be a clue to your overall health. Healthy nails are usually smooth and consistent in color. Specific types of nail discoloration and changes in growth rate can be signs of lung, heart, kidney, and liver diseases, as well as diabetes and anemia. White spots and vertical ridges are harmless.

Nail problems that sometimes require treatment include

  • Bacterial and fungal infections
  • Ingrown nails
  • Tumors
  • Warts

Keeping your nails clean, dry, and trimmed can help you avoid some problems. Do not remove the cuticle, which can cause infection.


Nail Diseases
Skin, Hair and Nails
... fungal infections Ingrown nails Tumors Warts Keeping your nails clean, dry, and trimmed can help you avoid some problems. Do not remove the cuticle, which can cause infection.
Skin Aging
National Library of Medicine
Aging Skin
Liver Spots
Wrinkles

Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it less plump and smooth. It might take longer to heal, too.

Sunlight is a major cause of skin aging. You can protect yourself by staying out of the sun when it is strongest, using sunscreen with an SPF of 15 or higher, wearing protective clothing, and avoiding sunlamps and tanning beds. Cigarette smoking also contributes to wrinkles. The wrinkling increases with the amount of cigarettes and number of years a person has smoked.

Many products claim to revitalize aging skin or reduce wrinkles, but the Food and Drug Administration has approved only a few for sun-damaged or aging skin. Various treatments soothe dry skin and reduce the appearance of age spots.

NIH: National Institute on Aging


Skin Aging
Seniors
Skin, Hair and Nails
Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it less plump and smooth. ...
Hives
National Library of Medicine
Urticaria

Hives are red and sometimes itchy bumps on your skin. An allergic reaction to a drug or food usually causes them. Allergic reactions cause your body to release chemicals that can make your skin swell up in hives. People who have other allergies are more likely to get hives than other people. Other causes include infections and stress.

Hives are very common. They usually go away on their own, but if you have a serious case, you might need medicine or a shot. In rare cases, hives can cause a dangerous swelling in your airways, making it hard to breathe - which is a medical emergency.


Urticaria
Skin, Hair and Nails
Immune System
Symptoms
Hives are red and sometimes itchy bumps on your skin. An allergic reaction to a drug or food usually causes them. Allergic reactions cause your body to release ...
Skin Infections
National Library of Medicine
Molluscum Contagiosum

Your skin helps protect you from germs, but sometimes it can get infected by them. Some common types of skin infections are

  • Bacterial: Cellulitis and impetigo. Staphylococcal infections can also affect the skin.
  • Viral: Shingles, warts, and herpes simplex
  • Fungal: Athlete's foot and yeast infections
  • Parasitic: Body lice, head lice, and scabies

Treatment of skin infections depends on the cause.


Skin Diseases, Infectious
Infections
Skin, Hair and Nails
Your skin helps protect you from germs, but sometimes it can get infected by them. Some common types of skin infections are Bacterial: Cellulitis and impetigo. ...
Rashes
National Library of Medicine
Contact Dermatitis
Dermatitis
Diaper Rash
Skin Rash

A rash is an area of irritated or swollen skin. Many rashes are itchy, red, painful, and irritated. Some rashes can also lead to blisters or patches of raw skin. Rashes are a symptom of many different medical problems. Other causes include irritating substances and allergies. Certain genes can make people more likely to get rashes.

Contact dermatitis is a common type of rash. It causes redness, itching, and sometimes small bumps. You get the rash where you have touched an irritant, such as a chemical, or something you are allergic to, like poison ivy.

Some rashes develop right away. Others form over several days. Although most rashes clear up fairly quickly, others are long-lasting and need long-term treatment.

Because rashes can be caused by many different things, it's important to figure out what kind you have before you treat it. If it is a bad rash, if it does not go away, or if you have other symptoms, you should see your health care provider. Treatments may include moisturizers, lotions, baths, cortisone creams that relieve swelling, and antihistamines, which relieve itching.


Exanthema
Skin, Hair and Nails
A rash is an area of irritated or swollen skin. Many rashes are itchy, red, painful, and irritated. Some rashes can also lead to blisters or patches of ...
Bruises
National Library of Medicine
Contusions
Contusion
Ecchymoses

A bruise is a mark on your skin caused by blood trapped under the surface. It happens when an injury crushes small blood vessels but does not break the skin. Those vessels break open and leak blood under the skin.

Bruises are often painful and swollen. You can get skin, muscle and bone bruises. Bone bruises are the most serious.

It can take months for a bruise to fade, but most last about two weeks. They start off a reddish color, and then turn bluish-purple and greenish-yellow before returning to normal. To reduce bruising, ice the injured area and elevate it above your heart. See your health care provider if you seem to bruise for no reason, or if the bruise appears to be infected.


Contusions
Skin, Hair and Nails
Injuries and Wounds
Symptoms
A bruise is a mark on your skin caused by blood trapped under the surface. It happens when an injury crushes small blood vessels but does not break the ...
Impetigo
National Library of Medicine

Impetigo is a skin infection caused by bacteria. It is usually caused by staphylococcal (staph) bacteria, but it can also be caused by streptococcal (strep) bacteria. It is most common in children between the ages of two and six. It usually starts when bacteria get into a break in the skin, such as a cut, scratch, or insect bite.

Symptoms start with red or pimple-like sores surrounded by red skin. These sores can be anywhere, but usually they occur on your face, arms and legs. The sores fill with pus, then break open after a few days and form a thick crust. They are often itchy, but scratching them can spread the sores.

Impetigo can spread by contact with sores or nasal discharge from an infected person. You can treat impetigo with antibiotics.

NIH: National Institute of Allergy and Infectious Diseases


Impetigo
Infections
Skin, Hair and Nails
Impetigo is a skin infection caused by bacteria. It is usually caused by staphylococcal (staph) bacteria, but it can also be caused by streptococcal (strep) bacteria. ...
Skin Cancer
National Library of Medicine
Actinic Keratosis
Basal Cell Carcinoma
Merkel Cell Cancer

Skin cancer is the most common form of cancer in the United States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, neck, hands, and arms. Another type of skin cancer, melanoma, is more dangerous but less common.

Anyone can get skin cancer, but it is more common in people who

  • Spend a lot of time in the sun or have been sunburned
  • Have light-colored skin, hair and eyes
  • Have a family member with skin cancer
  • Are over age 50

You should have your doctor check any suspicious skin markings and any changes in the way your skin looks. Treatment is more likely to work well when cancer is found early. If not treated, some types of skin cancer cells can spread to other tissues and organs. Treatments include surgery, radiation therapy, chemotherapy, photodynamic therapy (PDT), and biologic therapy. PDT uses a drug and a type of laser light to kill cancer cells. Biologic therapy boosts your body's own ability to fight cancer.

NIH: National Cancer Institute


Skin Neoplasms
Cancers
Skin, Hair and Nails
Skin cancer is the most common form of cancer in the United States. The two most common types are basal cell cancer and squamous cell cancer. They usually ...