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Skin Care Quiz - Terms and Concepts Inspired by Dr. Leslie Baumann, Paula Begoun, fellow Quizlet-Users, and the Internet

Information for these cards was taken from Dr. Leslie Baumann's book "The Skin Type Solution", Paula Begoun's website "Paula's Choice", Paula Begoun's "The Cosmetics Cop" podcast, several Skin Care card sets from here on Quizlet (thanks fellow Quizleters), Wise Geek (great site), and my own personal experience with sun damage and learning proper skin care. For the love of goodness, if you value your appearance, AVOID THE SUN!
What skin related problems arise directly as a result of sun exposure?
1. discoloration of the skin / uneven skin tone (hypopigmentation or hyperpigmentation, decrease or increase in skin pigment) 2. uneven pigmentation (solar lentigo / age spot, either brown, red or black in color) 3. dullness, rough texture (leathery skin) 4. dryness 5. wrinkles (fine lines and deeper wrinkles) 6. actinic keratosis (a precanerous overgrowth of skin caused by excess sun exposure) 7. rosacea 8. melasma (dark irregular patches on the face commonly caused by pregnancy) 9. thinning of the skin (visible veins, broken blood vessels) 10. brown bumps, white bumps (blackheads, whiteheads)
What is collagen?
Collagen is a protein fiber which gives structure to the skin. It can be thought of as the studs which form the basic structure of the skin and give it its framework.
What is elastin?
Elastin is an elastic protein in connective tissue that allows many tissues in the body to resume their shape after stretching or contracting
What is hylarunoic acid?
A type of polysaccharide, central to regulating cell growth and renewal. Found extensivelsy in connective, epithelial and neural cells. Binds readily with water and when injected under the skin provides an appearance of fullness
What are the 3 main components of the skin barrier?
ceramides, fatty acids, cholesterol
What are the 3 components of the oil secreted by the sebaceous (oil) glands of the skin?
wax esters, trigylcerides, squalene
What are Solar Lentigos?
In appearance, very similar to freckles, but caused predominantly by sun exposure over genes. They are completely preventable with sun avoidance and sun protection. [Lentigo : variant of the word "lentil"]
What often happens to people taking cholesterol lowering drugs?
They have drier skin as a result of the loss of cholesterol which is an essential component of healthy skin.
What is retinol?
It is derived from Vitamin A but has a different chemical structure.
How was retinol discovered?
It was discovered in 1978 by scientists who were researching treatments for Acne.
What is retinol used to treat?
Retinol has been proven to reduce fine lines, wrinkles, promote collagen production, accelerate the removal of dead skin cells by increasing the rate at which skin cells divide, consequently preventing the formation of brown spots as Melanocytes cannot produce pigment with the same speed at which skin cells are renewed. [Skin Type Solution, 15]
What are some of the brand names of retinol?
Renova, Avage, Retin-A
What are anti-inflamatories?
Ingredients which soothe the skin and reduce inflammation.
What are some natural anti-inflammatory ingredients?
Oatmeal, Feverfew,Licochalone, Green Tea, Chamomile, Cucumber extract, Calendula, Grapeseed Extract
What are antioxidants?
Antioxidants are ingredients which help to counteract Free Radicals (which damage cells through disruption of atomic structure). They can also be said to inhibit oxidation. They thus help the condition of the skin, and in food applications keep foods from becoming rancid and spoiled.
What are some antioxidants often used in skin care products?
Cucumber extract, Vitamin E, Coenzyme Q10, Grapeseed Extract
Are tanning beds safe or beneficial to the skin?
Tanning beds are terrible for the skin. The World Health Organization (WHO) has designated tanning beds as being a Level 1 Carcinogen, meaning they are as carcinogenic as Mustard Gas and Arsenic.
What is the most important thing you can do to keep your skin healthy and attractive?
What are exfoliants?
Exfoliants are products which help to remove the surface layer of skin, which is comprised of dead skin cells.
What is a good analogy for exfoliation?
A Pedicure. In a pedicure, dead skin cells are sanded off the heel of the foot using an emery board. After a pedicure the heel is smooth as a baby's bottom. Exfoliation accomplishes a similar function.
What is AHA and what are examples?
AHA stands for Alpha Hydroxy Acid. The most commonly used AHA's are Glycolic Acid and Lactic Acid.
What is the difference between AHA and BHA?
Generally speaking, BHA is a stronger exfoliant than AHA. It can exfoliate more vigorously, but presents greater risk of burning and damaging the skin. BHA can penetrate into the pores of the skin and exfoliate dead skin cells from inside the pores, which AHA cannot.
What is BHA and what are examples?
BHA stands for Beta Hydroxy Acid.The only example of BHA relevant to skin care is Salicylic Acid. Salicylic Acid is prevalent in products designed for treating acne.
What did Cleopatra purportedly use on her skin to maintain its radiance and uniformity of tone?
Sour milk. Sour milk contains Lactic Acid, which is an example of an AHA and thus a natural exfoliant for the skin. This was likely very helpful to Cleopatra for exfoliating off brown spots and other sun damage resulting from the desert climate of Egypt.
What is keratin?
A fibrous protein that occurs in the outer layer of skin and in horny tissues such as hair, feathers, nails and hooves.
Besides wrinkles, what is another skin problem which significantly detracts from the face and skin's appearance?
Dark spots. 21% of visits to the Dermatologist are for the treatment of dark spots.
What is melasma?
Melasma, also known as the "mask of pregnancy", consists of light or dark, brown or grey patches, ranging from the size of a dime, to large areas on the face and chest. It appears in sun exposed area, and more often in women during pregnancy or during estrogen replacement therapy.
What effect does estrogen have on the skin?
Increased levels of estrogen can result in unwanted dark spots on the skin; however, estrogen also works to maintain the skin's youthfulness. After menopause, women who do not take estrogen will find that their skin's appearance will decline rapidly. Health takes precedence though; do not take estrogen replacement therapy if it is contraindicated.
What is a wood's light? (also known as a black light or UVB camera)
A diagnostic tool whereby ultraviolet light (at a wavelength of ~ 365 nm) is shone onto the patients skin and shows any abnormalities as a fluroescence (light emitted from absorbing radiation). It reveals dark facial spots before they are visible to normal light.
What is most people's reaction to their skin's appearance upon exposure to a wood's light or UVB camera?
Most people are shocked by what they see. The vast majority of people do not wear sufficient sunscreen and the damage shows up as an array of dark spots covering the majority of the face. [Skin Type Solution, page
How can parents take advantage of the wood's light?
Parents who are concerned about their children's future appearance are advised to take their children (particularly teenagers) to a Dermatologist and allow them to see what their skin will look like in the near future. Hopefully that will communicate to them the folly of sunbathing, tanning beds and sun exposure in general.
What are ephelides?
Another term for freckles. They are typically associated with red hair and fair skin. The MC1R gene is believed to be the gene responsible for freckles and it is closely associated with red hair and fair skin.
What are melanocytes?
Melanocytes are the pigment (melanin) producing skin cells.
What is melanoma?
Cancer of the melanocytes.
What are the 2 methods of preventing unwanted skin pigment formation?
The first is to inhibit the enzyme tyrosinase (enzyme responsible for the formation of melanin), preventing the formation of melanin. The second is to stop the transfer of color into the skin cells. [Skin Type Solution]
What are some examples of tyrosinase (enzyme responsible for formation of melanin) inhibitors?
Hydroquinone, Arbutin, Licorice Extract, Kojic Acid
Is Hydroquinone safe to be used for a protracted period of time?
No. Hydroquinone should only be used for a maximum of several weeks, and should never be used by women during pregnancy. However, it is recognized as the most effective treatment for addressing unwanted dark spots. [Skin Type Solution]
What are some examples of ingredients which forestall the transfer of color into skin cells?
Niacinamide and Soy
What are ceramides?
Ceramides (Cera = wax) are lipids which form part of the skin barrier.
What is an Emollient (from L. mollire "to soften", related to the word mollify) ?
Emollients, also commonly referred to as Moisturizers, are products that help to soften skin or to treat skin that has become dry. Most emollients are forms of oil or grease, such as mineral oil, squalene, and lanolin. They work by increasing the ability of skin to hold water, lubrication of the skin, and providing skin with a layer of oil to prevent water loss. []
What is an Emulsifier [from L. "emulgere" = to milk out, from "ex" = out and "mulgere" = to milk]?
A surfactant that makes it possible for oil and water to mix (typically they don't) and form an emulsion [a colloid (mixture / suspension) where both phases are liquids].
What are Free Radicals?
Oxygen atoms or molecules with unpaired electrons that cause oxidation by stealing an electron from another molecule, damaging the molecules structure, and subsequently, the larger structure of which the molecule is a part (i.e. skin cell)
What is a humectant?
A substance added to another substance to keep it moist.
What is Glycerin?
A syrupy fatty alcohol formed by the saponification (the process of combining a fat and an oil to make soap through application of heat) of a fat and an oil. It is an excellent skin softener and humectant, and a very strong water binder. [Quizlet : Chapter 13 Skin Care Products by trujiloolga]
What are some natural preservatives?
Grapefruit Seed Extract, Citric Acid, Tocopherol (Vitamin E), Rosemary Extract
What are milia?
Small whitish lumps on the skin caused by clogged sebaceous glands. Milia typically occur on the face with the most common locations being around the eyes, face, across the nose and cheeks. In many instances, Milia disappear after a few weeks.
And to conclude finally : Are wrinkles a natural part of ageing?
To quote Dr. Leslie Baumann from The Skin Type Solution page 352, "Skin that NEVER SEES THE SUN does not wrinkle, so with the right behaviors wrinkles can be avoided...."
What is the skin barrier?
The outer layer of skin which helps the skin retain moisture. The skin barrier is like a brick wall, with each brick (or cell) held in place by mortar (fats called lipids).
What percentage of skin aging is a result of sun damage?
Ninety percent of skin aging is a result of sun damage
What is Sebaceous Hyperplasia?
What is a White Head?
What is an effective treatment for Sebaceous Hyperplasia?
BHA at 9%. [Cosmetic Cop Podcast, July 18th, 2012]
What is a Phtlate?
Phtlate's are used in nail polish and plastics. Phtlate's are illegal in Europe. [Cosmetic Cop Podcast, July 18th, 2012]
What effect does Alcohol have on skin?
Causes Free Radical Damage.
How long does it take to acquire the recommended daily intake of Vitamin D from the sun?
Exposing just an arm to the sun at noon during the summer for 20 minutes will provide the body with approximately 10,000 IU of Vitamin D.
UVA (Ultraviolet AGING) Radiation is a long wave radiation which can easily pass through glass and penetrates deeply into the skin, reaching the endodermis and damaging the skin's DNA. UVA Radiation is more insidious than UVB radiation, as it does not readily burn the skin, instead doing damage surreptitiously below the skin's surface, prompting the creation of new wrinkles and skin imperfections.
What is UVB?
UVB (Ultraviolet BURNING) Radiation is short wave radiation responsible for creating a Sun Burn, and limits damage to the top layer of the skin (epidermis)
What skin care behaviors can irritate the skin and cause inflammation?
Over scrubbing the skin, hot water, irritating skin-care ingredients (ALCOHOL, which is irritating for everyone, menthol, lime, eucalyptus, fragrances, essential oils : all of which are more of a concern for people with sensitive skin)
Why is inflammation so damaging to the skin?
What happens to skin as it ages?
The outer layer of skin get thick, and the underlying layer of skin gets thin, resulting in skin that looks rough and sagging in appearance. [Cosmetic Cop Podcast, July 18th, 2012]
What is the simplest skin-care practice one can do to dramatically and immediately improve the appearance of the skin?
Exfoliation : with either an AHA (Glycolic Acid) or a BHA (Salicylic Acid). Exfoliation removes the surface layer of skin much more effectively and efficiently than the body can do on its own, effectively "accelerating" the natural exfoliation process. The morning following the Exfoliation (after the skin has recovered from the momentary irritation), the skin WILL look markedly smoother.
What other beautification practice is analagous to Exfoliation?
A Pedicure. Scrubbing off the dead skin cells on the heel of the foot, results in the exposure of softer, smoother skin underneath. The heel looks brand new, practically baby smooth. The wrinkles are gone. The skin looks baby new. [Cosmetic Cop Podcast, July 18th, 2012]
What is Exfoliation?
Removing the dead skin cells on the surface layer of skin to reveal the smoother, younger skin cells underneath. The benefits of exfoliation can be seen "literally overnight." [Cosmetic Cop Podcast, July 18th, 2012]
Why is scrubbing skin damaging?
When you tear away at skin, it causes a wound healing response, causing inflammation, increasing blood flow to the wounded area and prompting the body to create scar tissue to protect the wounded area, resulting in skin which looks rough and not smooth in texture.
What is an additional benefit of exfoliating with AHA and BHA?
Use of AHA and BHA in addition to exfoliation, increases Collagen production and reformation.
What percentage of people wear sunscreen (both in sufficient quantity and frequency)?
10 percent [Cosmetic Cop Podcast, July 18th, 2012]
When the skin is exposed to UV radiation, Melanocytes (Melanin producing cells in the skin) produce increased amounts of the skin pigment Melanin as a mechanism of defense to help arrest radiation damage to the skin's cellular structures and DNA.
Is a Tan the body's way of trying to "look good"?
A Tan is a sign the skin has been DAMAGED. A Tan is a sign the skin has been trying to defend itself from the destructive effects of the sun's UV Radiation. A Tan is NOT the body's way of trying to "look good".
What are Cell Communicating ingredients?
What are Skin Identical ingredients?
What are Antioxidants?
Which skin-care ingredient is the most important?
There is no one particular skin-care ingredient which is more valuable than the rest. "Skin is complicated. Skin requires a cocktail of ingredients." [Paula Begoun, Cosmetic Cop Podcast, July 18th, 2012]
What is the goal of skin care for damaged skin?
Damaged skin (typically damaged by the sun) cannot produce many of the ingredients needed to maintain skin's youthful appearance, and so the goal of skin care products is to replace and replenish those ingredients to restore youthful skin.
After applying sunscreen, how much time should you wait before exposure to the sun?
Apply sunscreen 15-20 minutes before exposure to the sun to allow the cream sufficient time to form a proper barrier on the surface of the skin.
What is Genistein?
Genistein is a polyphenol found in soybeans and other plants that mimics the action of Estrogen in the body, helping to reduce the production of wrinkles; however, like Estrogen, it also promotes increased pigmentation of the skin.
What are the benefits of Vitamin C in skin care?
Vitamin C promotes Collage Synthesis and is an antioxidant.
Can cosmetic companies claim their products will physiologically improve skin?
Cosmetic companies cannot lay claim to their products having any "Biological Activity" because they would need to be classified as "drugs" by the FDA and be subject to clinical trials.
What is Glycerin?
An alcohol obtained by saponification of fats and oils
What are the benefits of Glycerin?
Glycerin acts as a humectant and an emollient to soften and smoothe skin
What is an emollient?
A substance which softens the skin [from Latin. "ex" = out and "mollire" = soften]
What is a humectant?
A substance that absorbs moisture [from Latin "umectare" = to moisen]
Is Ivory soap good for sensitive skin?
NO! Vigorously foaming soaps, like Ivory, are terrible for dry skin because they wash away the natural lipids that help your skin retain moisture. Any product that produces suds and foams contains detergent which is anathema for dry skin. [Skin Type Solution, 15]
What is Niacinamide?
A water soluble vitamin made from Niacin. Niacinamide and Soy help forestall the transfer of pigment from Melanocytes to skin cells, helping prevent formation of brown spots. [Skin Type Solution, 26]
What is the Epidermis?
The Epidermis [Gk. "epi" = over, "dermis" = skin] is the top layer of skin. When you look at someone's skin, you are looking at the very top layer, made of up of cells which reflect light. When the top layer is smooth, it reflects light evenly so that skin looks more uniform and radiant than when the surface is rougher. [Skin Type Solution, 18]
What is the Cell Cycle?
Basal ["from the base or bottom"] cells (or "Mother Cells"), the lowest portion of the Epidermis which produce all other Epidermal cells, divide into "Daughter Cells" which rise up to the higher levels of the Epidermis. As they travel, they age and die, so that the top layer consists of dead cells which naturally exfoliate off. [Skin Type Solution, 18]
How long does the Cell Cycle take?
Between 26 to 42 days. [Skin Type Solution, 18]
Between a person's 30's and 80's how much does the Cell Cycle slow down?
Between 30 to 50 percent of its pace in youth, meaning that older skin renews itself much more slowly, forming a rough surface of cells, rather than a smooth surface. [Skin Type Solution, 18]
What is Natural Moisturizing Factor?
A mixture of molecules (amino acids and salts) within the cells comprising the outermost layer of the skin. The molecules are hygroscopic [Greek. "hygro" = wet, "skopion" = to look at], attracting and absorbing water, thus hydrating the skin. []
What happens when skin is exposed to a dry environment?
Skin produces more NMF, but production takes several days to reach necessary levels, consequently skin may become quite dehydrated. This is why moisturizing is essential in a dry environment. [Skin Type Solution, 19]
Why do fingers and toes look wrinkled after sustained immersion in water but legs, arms, back, etc. do not?
Fingers and toes contain fewer lipids than other parts of the body making them more susceptible to the effect of sustained immersion in water removing significant amounts of Sebum causing skin to absorb more water thus swelling and appearing wrinkled. []
There are only a few sunscreen ingredients available which can protect skin from UVA ("Aging" Radiation) damage. What are they?
2 physical blockers : Titanium Dioxide (UVB & short wave UVA) and Zinc Oxide (UVB & short + long wave UVA). 5 chemical blockers : Avobenzone / Parsol 1789 (only protects against long wave UVA radiation. requires Octocrylene be present in a 2:1 ratio to remain photostable under sun exposure), Mexoryl SX (short wave UVA protection), Mexoryl XL (long wave UVA protection),
Tinosorb S (prevents photodegradation of other ingredients), Tinosorb M (triple-action protection : absorb, reflect, scatter UV light)
What is the different between Physical and Chemical sunscreens?
Physical sunscreens REFLECT sunlight. Chemical sunscreens ABSORB UV light.
Does a "Broad Spectrum UVA / UVB" sunscreen guarantee total UV protection?
No. The statement is vague and does not clearly specify if both Long-Wave and Short-Wave UVA radiation is blocked. The informed consumer will LOOK at the ingredients.
What does SPF refer to in relation to UVA and UVB radiation?
The SPF number refers to the degree of protection the sunscreen offers from UVB ("Burning") radiation. It does NOT have any bearing on UVA ("Aging") radiation protection.
REFERENCES used. (partial list of references used)
Tinosorb S and M []
What does the SPF (Sun Protection Factor) number on the sunscreen bottle indicate?
SPF indicates length of time a person can remain in the sun without burning (e.g. THEORETICALLY, a person who burns in 10 minutes using a sunscreen with SPF 15, can remain under the sun for 150 minutes). Practically, an SPF of 15 will last around an hour. []
When are the sun's rays at their most potent (and most importantly avoided)?
Between 10 am and 4pm
What is an Occlusive?
Materials such as oils and waxes which cannot be penetrated by water. Occlusives are spread onto skin to form a film which shields it to slow and prevent moisture from evaporating. []
What are some examples of Occlusives?
Classic examples are petrolatum and lanolin. For sensitive skin, dimethicone and shea butter.
What is Dimethicone?
A silicone oil which forms a slick, lubricating coat on a surface. Can be used in hair products to create a surface with less friction for easier combing, or as a protectant, emollient, and occlusive for skin care products.
What are some examples of Emolllients?
Cetearyl Alcohol, Isopropyl Myristate, Triglyceride, Myristic Acid, Palmitic Acid, PEG-60 Hydrogenated Castor Oil, Glyceryl Linoleate, Cyclomethicone, Dimethicone, Decyl Oleate, and Stearic Acid. Natural Emollients include : Lanolin, Plant Oils (Jojoba), Aloe Vera, Shea Butter, and Cocoa Butter. []
What is Lanolin?
Lanolin is an oily, yellow substance produced by the oil glands in a sheep's skin. It coats the sheep's wool, acting as a waterproof barrier, as a result, when the sheep are in inclement weather for hours, they are less affected by the cold. Known in Greek and Roman times, it was noticed that sheep farmer's had smooth, well-hydrated hands, so use of Lanolin became widespread. []
What is the name of the product Shania Twain famously uses as a moisturizer?
Bag Balm, a moisturizing product used for udder soreness in cows and chapped hands in farmers. Known for its ability to address dry skin conditions like eczema and psoriasis. It contains petrolatum, lanolin, and an antiseptic. [Skin Type Solution, 304]
What is Petrolatum?
Also known as Petroleum Jelly and Soft Paraffin. A semisolid mixture of hydrocarbons obtained from petroleum; used in medicinal ointments and for lubrication [WordWeb software program] Used to seal a cleaned burn or injury off from contamination, and as skin care product to seal in moisture. []
Is Petrolatum safe?
The major concern is the presence of PAH's (Polycyclic Aromatic Hydrocarbons) in unrefined petrolatum. Consumers should look for USP grade Petrolatum (BP in Britain and Ph.Eur in Europe) indicating the petrolatum meets specific purity standards, and buy trusted brands, like Vaseline.
What are the benefits of BHA?
BHA is preferred for oily, acne-prone skin and for treating blackheads and white bumps because it can penetrate the oil clogging pores, normalizing the lining of the misshapen pore contributing to acne. BHA has anti-inflammatory and antibacterial action, as a result, BHA is preferred for those struggling with Rosacea. []
What are the benefits of AHA?
AHA exfoliates by loosening the bonds between dead corneum cells by dissolving the intercellular cement (lipids) holding them together. AHA's also improve moisture content. AHA's are preferred for sun damaged and dry skin because they exfoliate on the surface of the skin. []
What is a Comedone?
A thickened secretion plugging a duct of the skin, especially of a sebaceous gland [from L. "com" = with, "edere" = eating ; literally = glutton] []
What is a Blackhead?
Blackheads (also called Comedones) are an accumulation of sebum, keratin, skin debris and bacteria within a hair follicle. Follicles in the skin become blocked with sebum, causing the follicle to widen, and collect dead skin cells and bacteria. Blackheads, in contrast to Whiteheads, are open to the air, causing the oils to oxidize, turning them brown (similar process to an apple browning with exposure to oxygen). []
What is a Whitehead?
Identical to a Blackhead, with the exception that a small amount of skin has grown over the follicle, resulting in the bump appearing white. []
What is Rosacea?
A chronic skin disease which affects adults (more often women) in which blood vessels of the face swell resulting in a flushed appearance. [WordWeb software] Ruddiness, redness of the cheeks, chin, and forehead are common symptoms. Flares up in intervals. [[
What is Erythema?
Superficial reddening of the skin, usually in patches, as a result of injury, irritation, or sunburn causing dilatation of the blood capillaries. [from Gk. "erythros" = red]
What is a Cell-Communicating Ingredient?
Theoretically, they are ingredients that have the ability to induce a skin cell to look, act, and behave better, more like a normal healthy skin cell, or concurrently blocking substances which persuade skin cells to behave in a destructive manner []
What are some Cell-Communicating Ingredients?
retinol, retinaldehyde, retinoic acid, epigallocatechin-3-gallate, eicosapentaenoic acid, niacinamide, lecithin, linolenic acid, linolenic acid, phospholipids, carnitine, carnosine, adenosine triphosphate, adenosine cyclic phosphate, palmitoyl oligopeptide, palmitoyl tripeptide-3 (and most other peptides), and pyrus malus (apple) fruit extract []
What is Squalene?
Squalene is a natural organic compound produced by all plants and animals including humans. Produced in the liver, it is found in sebum, and helps keep hair flexible and the skin retain moisture. []
What is the Stratum Corneum [from L. "stratum" = layer, "cornus" = horn] ?
The horny outer layer of the Epidermis, consisting of several layers of flat, keratinized (replete with the protein keratin thus becoming horn-like in texture), nonnucleated, dead or peeling cells. []
What are some recommended Sunscreen brands which provide superior UVA / UVB protection?
Cliniderm Protective Lotion SPF 45 : Titanium Dioxide USP 6.6%, Zinc Oxide USP 6.1% (does NOT whiten skin!) , Blue Lizard Sensitive SPF 30+ : Titanium Dioxide 5%, Zinc Oxide 10% (bottle changes color when exposed to UV light!), Ombrelle Face SPF 60 : Octocrylene 10%, Titanium Dioxide 4.15%, Avobenzone 3.5%, Mexoryl XL 3%, Mexoryl SX 3% [DOES whiten skin some], Eco Sunscreen Face SPF 30+ : Zinc Oxice 20% [NOT tested on animals! does whiten skin though]
What does USP stand for and why is it important?
USP = United States Pharmaceutical. The USP was founded in 1820 to combat inconsistent drug quality and protect the public health; to create a system of standards to help ensure medication quality and uniformity in the United States. Official USP standards are legally enforceable by the U.S. Food Drug and Administration (FDA) for drugs imported to or marketed in the United States. USP establishes both written standards and physical USP Reference Standards. []