Since its discovery more than thousand years ago, salicylic acid has been widely used as an anti-inflammatory drug. It is notable for its ability to alleviate aches and lessen fevers. The concept of skin treatments is nothing new, and in line with the increasing demands for cosmetic treatments to enhance the appearance of the skin, specialists have formulated many new skin treatments for patients to choose from. One of which is the use of salicylic acid as an agent for the chemical peeling procedure.
Chemical peeling uses controlled damage to the skin’s surface to promote rejuvenation, which leads to improving the structure of the skin visibly. It is used for treating patients with various types of skin diseases such as acne, dandruff, seborrhea, or psoriasis, and to remove corns, calluses, and warts. Accordingly, there are three basic types of chemical peels: superficial, medium-depth, and deep. Salicylic Acid is a good agent for peeling because of its stratum corneum (outermost layer of the skin) exfoliating capacity. Salicylic acid has a lot of uses, but many who use it are not aware of the safety and precautionary measures needed to prevent future complications. This article digs into the efficacy, procedure, properties, purpose, and side-effects of salicylic acid as a dermatological agent.
Chemical Peeling
Chemical peeling is also known as chemexfoliation. This technique is widely used to enhance the appearance of the skin on the face, neck, arms or hands. A chemical peeling agent (salicylic acid) is applied to the skin, which promotes accelerated skin exfoliation and eventually peeling off of the superficial layers of the skin. This procedure unveils a regenerated skin which is usually smoother and less wrinkled than the previous layer.
Types of Chemical Peel
Superficial peel
This type of chemical peeling is mostly achieved by topical ingredients or treatments, such as microdermabrasion, instead of a peeling procedure. Research suggests that exfoliation triggered by topical ingredients can be perceived as sensitivity or flaking skin, and decent discussion and justification from the dermatologist is necessary to ensure compliance in the initial days of using an efficient topical peel. For a true epidermal peel to be attained, it is necessary to have the treatment in a clinic using a variety of topical ingredients. To only penetrate the superficial layer of the skin and gradually exfoliate it, Alpha-hydroxy acid or another mild acid is typically used.
Medium-depth peel
To infiltrate the external and middle layers of skin to remove impaired skin cells, glycolic or trichloroacetic acid is applied. Trichloroacetic acid is also known as trichloroethanoic acid or tichloromethane carboxylic acid. It has been a part of the aesthetic industry for centuries and is commonly used both as a single ingredient peel and in combinations.
This procedure is used to enhance age spots, fine lines and wrinkles, freckles, and moderate skin discoloration. It can also be used to restore rough skin and to treat some precancerous skin growths, such as actinic keratosis.
Deep peel
Of all the peels, deep chemical peels are the strongest. The treatment can only be executed once and is usually used on the face. Phenolic acid is used for this type of peel. This is used to treat coarse facial wrinkles, blotches due to aging or exposure to the sun, and pre-cancerous growths. The treatment also removes freckles and shallow scars. This is the most dramatic, longest-lasting peel and takes longer to complete than other peels (about one to two hours per session).
It also requires the most healing time. In return, patients see an intense improvement in skin appearance. Advice from an experienced cosmetic dermatologist is necessary for potential patients before undergoing the procedure, as a deep chemical peel may cause long-lasting lightening of the skin.
Origin of Salicylic Acid
The utilization of salicylic acid as a medical treatment was first seen around 500 BC in the records of the ancient Greeks. Back then, salicylic acid wasn’t used as an agent to resolve acne issues or skin exfoliation. Instead, it was used predominantly to relieve pain and fever. It has also been noted that Native Americans used salicylic acid in the form of willow bark, for pain, fever, and inflammation.
In the first century, scientists such as Hippocrates, Celsus, Pliny the Elder, Dioscorides, and Galen began studying willow bark, its properties, and its active ingredient, salicylic acid. In 1763, willow bark was used by Edward Stone in the treatment of malarial fever. It was the first “clinical trial” and it was a success.
Then in the late 1820s, Buchner, Brugnatelle, and Fonatana began isolating the salicin from willow bark in a process that was later improved by Leroux. In the 1860s, the softening and exfoliating capacity of salicylic acid was discovered. Salicylic acid was then used as a component of many topical acne medications, due to its comedolytic and enhancement properties.
Properties and Uses of Salicylic Acid
Salicylic acid is a colorless, crystalline, organic carboxylic acid that melts at 159oC. It is ethanol and ether soluble but is only slightly water soluble. Sources of salicylic acid, aside from willow bark, are sweet birch and leaves of wintergreen. Commercially, it is formulated under heat and pressure with phenolate and carbon dioxide, which is then treated with sulphuric acid for liberation.
In addition, salicylic acid is miscible with epidermal lipids and sebaceous gland lipids in hair follicles because it is a lipid-soluble agent. Salicylic acid’s ability to remove intercellular lipids which are associated with the surface of the epithelial cells is due to its lipophilic properties. Dermatologists frequently use this anti-hyperplastic effect of salicylic acid on the epidermis in chemical exfoliation of the skin. This aspect is considered a therapeutic effect and is the reason why it can decrease the sebum secretion of patients with acne.
The adhesion of skin’s epidermal cells relies on the desmosomes (a specialized cell structure for cell-to-cell adhesion), where proteins, specifically desmogleins (adhesion proteins) are part of its structure. Considering that salicylic acid is an organic acid, it can remove the desmosomal proteins, including the desmogleins. This event results in loss of cohesion of epidermal cells, which then leads to skin exfoliation. This is why salicylic acid is considered a desmolytic agent instead of being a keratolytic agent because it functions by dismantling cellular joints instead of destroying the filaments of the intercellular keratin.
Salicylic acid is a main component of Aspirin, which has the chemical name of acetylsalicylic acid. It is a substance which is recognized as an analgesic and antipyretic, causing inevitable inhibition of prostaglandin synthesis. It was invented by Charles Gerhardt in 1853, but the Bayer Company did not immediately sell it into the market until they patented the formula in 1899.
Aside from being a skin peeling agent, derivatives of salicylate are used as components of sunscreen formulations. It has both anti-microbial and anti-fungal properties. Salicylic acid also softens the skin, and can be applied in varying amounts for the removal of dead skin cells on the skin’s surface. Since salicylic acid has inflammatory properties, it can also soothe the skin. In addition to that, it has been observed that salicylic acid also has an anesthetic effect, which is present in the peeling procedure of the skin. This boosts the ability of the patient to tolerate the procedure.
Who is A Candidate for Chemical Peel?
Patients with fair skin and light hair, in general, are the best candidates for chemical peel procedures. However, good results can still be attained in individuals with other skin pigmentation and hair color. Individuals who are not satisfied with how their skin looks, have realistic expectations of the treatment, and do not smoke are usually the best candidates for the procedure. The patients who can undergo chemical peels should be in good physical health, understand the procedure, and have realistic expectations of the outcome.
If your aim is to alleviate acne, smoothe wrinkles, improve skin texture, eliminate age spots, or reduce the damage caused by overexposure to the sun, then you will probably be pleased with the results. There are three basic types of chemical peel that you can opt to choose from. They vary in strength and offer diverse levels of treatments. For better results, ask your doctor about the best type of chemical peel for your skin type and needs.
Contraindications
It has been found that salicylic acid peels are safe and well tolerated by all racial or ethnic groups ranging from light to dark skin types. Some of the potential contraindications to salicylic acid peeling are enumerated below.
- Active dermatitis at the peeling site
- Active infection or acute viral infection
- Contact allergy to salicylates
- Pregnancy
- Skin malignancy
- Tanned skin
- Use of isotretinoin (an oral pharmaceutical drug primarily used to treat severe nodular acne) during the 3 to 6 month peeling procedure
Safety and Precautionary Measures During Pregnancy
The US Food and Drug Administration (USFDA) classifies salicylic acid as a pregnancy category C drug (drugs that do not have enough research to determine if they are safe). The use of salicylic acid peels during pregnancy is not suggested because salicylic acid’s configuration is closely related to that of aspirin, which has been associated with miscarriage, birth defects, bleeding complications, and salicylism.
Are Chemical Peels Painful?
Throughout the light or medium chemical peels, patients generally feel a mild stinging sensation. The dermatologist may suggest intake of a mild pain reliever to get rid of any discomfort after the procedure. A deep peel may result in significantly more discomfort than a light or medium peel.
Cost of the Procedure
The cost of chemical facial peels differs from state to state and physician to physician. Roughly, the existing chemical peel price ranges from $600 to $900. But keep in mind the possible added expenses, especially with intensive chemical peels. These include the cost of usage of the surgical facility, cost of anesthesia, and probably a stay in the hospital.
The factors to consider when trying to estimate the final cost of your procedure are the type of peel that you want, your skin condition, and other aspects unique to your circumstances. The cheapest of all the peels is the light chemical peel which can cost as little as $150. On the other hand, deep chemical peels are generally the most expensive. Its price can go up to $6000 for every session.
Pre-peeling Preparations
IT is required that you undergo an evaluation of your skin’s condition and your expectations before seeking a chemical peel procedure. The dermatologist must assess the patient for probable symptoms, look for any contraindications, discuss the aspects of the treatment, and evaluate the patient’s expectations of the outcome. In addition, discussion about the potential risks of the treatment as well as the restrictions must be done.
There are a few different types of classifications used to assess a patient’s evaluation. Fitzpatrick’s classification is a numerical classification schema for human skin color, which is used to determine skin type. Glogau classification was developed to objectively measure the severity of photoaging and wrinkles, and is used to determine the level of photoaging.
A detailed medical history and examination must be implemented for all patients prior to chemical peel. The areas that will undergo the procedure should also be photographed, including the full-face frontal and adjacent views. Informed consent must be signed prior to performing the peeling procedure. Individuals who will undergo the procedure should be instructed that it is necessary to avoid smoking, minimize their contact with sunlight, and be consistent in sunscreen application. Management for pre-peel varies depending on the skin condition being addressed.
Peeling Procedure
The chemical peel procedure involves the use of a 20% or 30% salicylic acid formulation in an ethanol base. The peels can be applied repeatedly with rest intervals of 2-4 weeks. Depending on the skin type and severity of the condition being treated, peak results can be seen after a series of 3-6 chemical peels.
In order to evaluate the sensitivity and reactivity of the patient’s skin to the peeling agent, it is wise to perform the peel initially with a 20% salicylic acid formulation. The face should be thoroughly cleansed with alcohol to remove visible skin oils before starting with the procedure. Then the procedure is performed and can be done in various manners and methods of application.
Most individuals complain that during the procedure, mild burning and a stinging sensation occur. If portable ice packs are used, the burning and stinging sensation can be reduced. A white precipitate is formed within 30 seconds to 1 minute of peeling. This is the effect of the crystallization of the salicylic acid. When this happens, it means that after the treatment the patient should expect some crusting and peeling. This crusting and peeling may be quite useful for treating patients with photodamaged skin, but there should be minimal or no frosting preferred for patients with melasma and dyschromia.
The appropriate contact time for the peel differs, but is usually within the range of 3–5 minutes. After the peel has reached the appropriate contact time, the face is then rinsed thoroughly with tap water. To remove any salicylic acid precipitate residues, a mild cleanser can be used. At the end of the treatment, a mild moisturizer is applied to the treated area.
Post-peeling Care
It is essential for every patient to remember that sun exposure and smoking after a chemical peel must be avoided. These can cause unwanted side effects, including infection and scarring. The use of mild moisturizers and cleansers are continued for the first 48 hours post-peel, or until the irritation has halted.
Then the patients can start again in the application of their formulations for topical skin care, which may consist of retinoids, topical demenalizing agents, or topical anti-acne medications. Treatment with low to high potency topical steroids can be administered if there will be series of excessive exfoliation and inflammation. Topical steroids have the ability to alleviate post-peel inflammation and decrease post-inflammatory hyperpigmentation.
Benefits of Skin Exfoliation
Clogged pores
Exfoliation helps to get rid of congestion, otherwise known as blackheads and whiteheads, if you are experiencing clogged pores. These are commonly found on the nose, chin, and forehead. For better results, do the procedure no more than twice a week.
Dry skin
Scaly or flaky areas caused by the skin becoming too dry or dehydrated would benefit immensely from exfoliation. After you have exfoliated an area of dry skin, you can put on a moisturizer to the new and soft skin cells.
Skin pigmentation
Skin pigmentation basically affects the color of the skin. This disorder comes along with different factors like aging, pregnancy, or hormonal imbalance. Affected areas get darker as your age progresses. When exfoliation is used, the skin pigments are shattered and tend to disappear.
Younger looking skin
Aging skin endures a lot of changes. With time, it thins, falls, and wrinkles along muscular and gravitational folds. Associated with the effects of simple aging on skin, sun damage leads to additional problems, including thickening, solar elastosis, and subsequent pigmentary abnormalities. A facial chemical peel is one of the greatest methods you can use to have the wrinkles treated in most of the cases.
The exfoliation of the superficial layer of the skin caused during a chemical peel will allow for a large extent of wrinkles and aging to be reduced, if not completely erased. This is most effective when performed during early signs of aging before the damage has become too extensive.
Holistic health and well-being
There are a lot of benefits from exfoliation aside from having gorgeously soft skin that can absorb a good moisturizer readily. It can also aggregate the circulation of the blood and the lymphatic system, which is advantageous for the body. This event boosts the build-up of new skin cells, decreases the number of fatty tissues, and helps to eliminate toxins.
Side-Effects
When executed by a qualified cosmetic dermatologist or plastic surgeon, chemical facial peels are harmless. The side effects of deep chemical peels are normally more prominent, and recovery time is longer. However, serious side-effects are rare when the procedure is performed by a qualified doctor and safety precautionary measures are met. Enumerated below are a few possible side-effects of salicylic acid peeling.
Contact Allergy
Salicylic acid is a weak contact sensitizer. There are very few cases of allergic reaction to salicylic acid. IN addition, patients who experience allergic contact dermatitis on exposure to salicylic acid preparations may not be allergic to salicylic acid, but may be allergic to other mechanisms of the treatment.
Salicylism
Salicylism is an acute or chronic poisoning caused by aspirin or other salicylates. When applied topically to the skin, salicylic acid is absorbed readily within 24 hours. It can already be detected in the urine. When incorporated with a hydrophilic base, the consumption of salicylic acid can be improved topically. Though it is rare to happen, systemic toxicity can be a serious concern.
Systemic toxicity may occur due to the absorption in the cutaneous membrane of the skin. The salicylates are lethal to the central nervous system in high concentrations. If taken by the body in these high concentrations, toxicity may lead to nausea, vomiting, dizziness, psychosis, stupor, and consequently coma or even death. Associated tinnitus can be the effect of a rise in labyrinthine pressure. A trigger can occur in the medulla’s respiratory center, and manifests as evident hyperventilation. This can lead to respiratory alkalosis. Metabolic acidosis can also happen in infants and children.
Hypoglycemia
Hypoglycemia is characterized by the deficiency of glucose supply in the bloodstream. Glucose metabolism and its utilization in cells can be distressed by systemic absorption of salicylates which can then lead to hypoglycemia. Individuals with uremia are the most likely to experience this side-effect.
Other risks and side-effect include:
- Crusting and drying of the skin’s surface
- Extreme exfoliation
- Pigmentary dyschromia – refers to an alteration of the color of the skin or nails, “Hyperpigmentation”
- Prolonged erythema – a reddening of the skin due to inflammatory or immunologic procedures
- Reactivation of cold sores
- Scarring
- Systemic poisoning
- Temporary or permanent change in skin color, particularly for women on birth control pills, who subsequently become pregnant, or who have a history of brownish facial discoloration.
Salicylic Acid Conclusion
When applied correctly, salicylic acid is a harmless and effective exfoliating agent. It is one of the most gentle chemical peeling agents on the market today. It is the answer to a number of problems in dermatology and cosmetics, including acne vulgaris, melasma, photodamage, freckles, and lentigines.
It can be used for a wide range of skin types, from light to dark. It is still continuously being studied by researchers and has new formulations which contain polyethylene glycol. These new formulations have been applied to mice which were able to avert skin tumor formation, making it a promising exfoliating agent for use in the future.
