Glossary of Skin Care Terms


A skin condition that manifests itself in the form of blackheads, whiteheads, pimples and/or cysts; lesions which are thought to result from the accumulation of keratin proteins, bacteria and oil in hair follicles.


A substance that has an opposite reaction to acid and is capable of neutralizing it.


Foreign substances that cause allergic reactions. Examples of allergens are plant pollens, dust mites, animal dander, foods, insect venom, antibiotics, and substances such as latex and rubber


An acquired sensitivity to a substance. When allergic reactions occur following external contact, they usually produce eczema-like dermatitis, usually characterized by redness, itching and swelling.


Medicine used to counteract histamine, a chemical released by the body in an allergic reaction that contributes inflammation. Some examples include (Benadryl) and hydroxyzine (Atarax). Many may cause drowsiness.


Antioxidants are substances that may protect your cells against the effects of free radicals. Free radicals are molecules produced when your body breaks down food, or by environmental exposures like tobacco smoke and radiation. Free radicals can damage cells, and may play a role in heart disease, cancer and other diseases.


Airway disease characterized by recurrent breathing problems. People with asthma have acute episodes when the air passages in their lungs suddenly narrow, and breathing becomes more difficult. Sometimes, asthma attacks are triggered by allergens, but infection, exercise, cold air and other factors are also important triggers.


An agent that is capable of shrinking and contracting skin tissue, temporarily and locally.

Atopic dermatitis

Also called eczema, this is a chronic, recurring inflammatory skin disorder that usually first appears in babies or very young children and may last through adulthood. Eczema causes the skin to itch and develop a red, scaly, patchy rash. It often develops in people who have hay fever or asthma or who have family members with these conditions.

Atopic triad

Atopic dermatitis (commonly called eczema) forms part of what is known as the atopic triad, which also includes hay fever (allergic rhinitis) and asthma. It is a medical term doctors use to refer to these 3 allergic disorders: asthma, hay fever or allergic rhinitis, and atopic dermatitis.

Atrophy (skin)

Thinning of the skin.

Borage oil

Comes from the seeds of the borage (Borago officinalis) plant.


A substance derived or extracted from a plant.


Long-lasting and occurring over and over again or characterized by long suffering; referring to a disease or disorder that lasts for a long time.

Coal tar

A byproduct obtained from bituminous coal.


A fibrous protein in the skin that gives it its firmness. When the collagen fibers are stretched or strained, the skin loses its elasticity and the area wrinkles and sags. Collagen is used in skin care products because of its moisture binding properties.


Blackheads. More evident in acne-prone skin.


A semisolid mixture of oil and water that is mostly oil and is intended for topical use.


Inflammation of the skin.


Connective tissue layer under the epidermis. Contains blood vessels, nerves, glands and hair follicles.


A type of skin condition with redness, itch, bumpiness, and scaling (see atopic dermatitis)


Flexibility; the ability of your skin to stretch and spring back.


Elastin is the protein that gives skin its elasticity.


An ingredient that softens, smoothes and moisturizes the skin.


An agent used to combine two liquids that ordinarily do not mix, such as oil and water.


The outermost layer of the skin where skin cells are formed, mature and die. Contains Epidermal cells.


An ingredient or product that is used to remove, or exfoliate, dead cells from the skin’s surface.


Slough off dry, scaly skin.


A term used to describe when eczema worsens (itching and redness).


A deep, narrow, tube-like channel in which a hair grows. The opening of the channel on the skin surface is the pore.


A compound (a combination of two or more elements) made of volatile (evaporates at room temperature) chemicals that create an odor. Fragrances and perfumes are typically comprised of dozens or even hundreds of synthetic chemical compounds. See the SOA Advisory on Fragrances and Perfumes.

Free radicals

Unstable reactive molecules that can initiate a chain reaction of gradual damage to skin cells. They are generated through UV exposure, smoke, and other pollutants – and can be prevented primarily through the use of antioxidants and sunscreens.

Gamma linoleic acid

An essential fatty acid in the omega-6 family that is found primarily in plant-based oils.

Homeopathic remedies

Treatment based on homeopathic principles. Homeopathy views symptoms as the body’s natural reaction in fighting the illness and, unlike conventional medicine, seeks to stimulate rather than suppress them.


A substance that promotes the retention of moisture.


To add moisture.

Hydrophilic Systems

Water based aqueous systems (as opposed to “oil” based systems).


Formulated to reduce the chance of allergic reactions by avoiding ingredients that are most likely to cause these problems. Does not mean that allergic reactions are not possible, only less likely.


Any substance that influences the immune system; a substance or process capable of modifying functions of the immune system.


The body’s natural response to injury or abnormal stimulation by a physical, biologic, or chemical agent. Typical signs of inflammation include pain, itchiness, warmth, redness, and loss of function.


A tough, fibrous protein found in the surface cells of the skin, hair and nails.

Lipid Barrier Restoration

Elements reintroduced into skin to reinforce the intercellular lipid barrier, which is responsible for moisture retention.


Fatty substances that help bond skin cells together and strengthen the skin. Lipids also help skin retain moisture.


A semisolid mixture of oil and water that is mostly water and is intended for topical use.


The pigment produced by the skin cells known as melanocytes. The amount and size of the melanin granules is what determines the skin’s color, or skin tone. Melanin is also a natural defense against ultraviolet radiation.


Something that will make skin softer and more pliant by increasing its hydration. Also called emollient.


Understood to mean that the product is formulated with ingredients that originate or are extracted from substances that were once living. Examples of natural substances include fruit, vegetable and herbal extracts and witch hazel.


Minimizes potential to cause acne.


A clear, greasy semisolid (contains no water) preparation that is intended for topical use.


Taken by mouth (for example, a pill)

Oral immunosuppressant

An oral medication that prevents or suppresses a response by the immune system.


A drug that can be purchased without a prescription.


The level of acidity or alkalinity of a solution or substance. If the pH of a product is too different from the pH of the skin it could damage the skin. It is estimated that the ‘natural’ skin surface pH is on average 4.7.


Refers to accelerated signs of aging, which are caused by overexposure to sunlight.

Phototherapy (ultraviolet therapy)

Therapeutic use of ultraviolet light.


Something that looks like a drug and is used like a drug but that has no active ingredient; often used to test the efficacy and safety of prescription medications in clinical trials.


Substances that promote the growth of good bacteria in the intestines. Probiotics may reduce allergic reactions by improving digestion or by influencing the immune system, or both.


Essential components of living tissues. Used in cosmetics for conditioning properties.


Not responsive to usual treatments.


Able to resume its original shape after being bent, stretched or creased; elastic.


The skin’s own oil. It serves as a natural moisturizer. Sebum is produced by the sebaceous glands and secreted through the hair follicles.


An agent capable of dissolving another substance. Water is the most common solvent.


Glucocorticoid steroids are used as anti-inflammatory treatment for eczema. These steroids can be topical or oral. They are different from the anabolic steroids used by some athletes.


Does not contain a steroid.

Stratum Corneum

Outermost layer of the epidermis, composed of non-living protein.


Stretch marks.

Surfactant / Surface active agent

Any compound that reduces surface tension when dissolved in water solutions, or between a liquid and a solid. In personal care products these typically act to remove oil from the skin.


Anything that a patient experiences that may indicate a disease.


Involving the whole body.

T cells

Also known as T lymphocytes, T cells are a type of white blood cells involved in rejecting foreign tissue, regulating immunity, and controlling the production of antibodies to fight infection.


Pertaining to the surface of the skin; a medication applied to the skin.


A term to describe the flow characteristics of a product. Also commonly used to describe how thick or thin a liquid is.


Get the latest eczema news delivered to your inbox.