Acne Medications and the Sun

A popular belief is that sunlight is a good treatment for acne because it helps to “dry out” the face and reduce the oiliness that can cause acne. But the sun can actually cause an adverse skin reaction if using certain medications. Sunlight can initiate a reaction with the chemicals in certain medications causing a photosensitive reaction on the skin. This article will describe some basic terms that explain how sunlight can damage the skin when combined with certain medications with a specific focus on acne medications.

What Is Photosensitivity?

Photosensitivity is an abnormal reaction of the skin in response to exposure to natural sunlight or UV radiation. Photosensitive, phototoxic and photoallergic reactions, can occur as a result of sun exposure after ingesting systemic oral medications and/ application of topical preparations.^[1] Usually, a widespread reaction suggests a reaction from an oral photosensitizer, whereas a localized reaction is indicative of a topical photosensitizer.^[1]

Photoallergic

A photoallergic reaction occurs when ultraviolet rays from the sun alter the structure of a drug. When this occurs, the body recognizes it as an invader and mounts an immune response. This allergic response causes redness, itching, inflammation and swelling in sun exposure areas 24-48 hours after exposure.^[1] It can appear on both sun-exposed areas and extend beyond areas that have not had direct sun exposure.^[2] The skin reaction typically resolves after discontinuation of the offending medication, but on occasion, can persist despite discontinuation.^[2]

Phototoxic

Phototoxic dermatitis is an inflammatory skin reaction in response to photoactive chemicals without an immune response.^[1] In phototoxic reactions, a drug may become activated by exposure to sunlight. The photo-active drug can create free radicals, which accumulate in the skin and cause cell damage.^[1] In response, the skin will form an immediate sunburn-like reaction. This reaction will present only on sun-exposed areas shortly after exposure and resolves when the offending drug is discontinued.

Acne Medications That Cause Photosensitivity

There are many different treatments for acne. They can be in the form of pills, face washes, topical creams, lotions or gels. Many acne treatments function by stripping the outer layer of the skin, the stratum corneum. This layer gives some protection against ultraviolet radiation. So, when it is gone, the skin becomes more sensitive to the sun.

Topical Retinoids

Retinoids are a family of compounds derived from Vitamin A that when applied topically cause skin cells to grow (divide) and die more rapidly, which increases cell turnover.^[4] These agents are a commonly prescribed topical treatment for acne. They are effective in both the treatment of inflammatory acne lesions and helping to prevent the formation of comedones (“pimples”) by unclogging pores.^[5] One of the complications of acne is scarring and hyperpigmentation. Since retinoids work as an exfoliating agent by increasing cell turnover, they may help to reduce the appearance of scarring and hyperpigmentation. However, this exfoliating property removes the outer layer of the skin, the stratum corneum, which causes the skin to become dry, itchy and scaly. The lack of protective skin barrier causes an increase in sensitivity to the sun.^[5]

Common acne medications containing retinoids include:

• Atralin^® (tretinoin)
• Avita^® (tretinoin)
• Differn^® (adapalene)
• Epiduo® (adapalene and benzoyl peroxide)
• Epiduo-Forte^® (adapalene/ benzoyl peroxide topical)
• Retin-A^® (tretinoin)
• Retin-A Micro^® (tretinoin micro)
• Tazorac^® (tazarotene)
• Ziana^® (clindamycin phosphate, tretinoin)

To avoid adverse phototoxic reactions, many dermatologists recommend that the application of medications containing retinoids should be followed by the application of good moisturizers and sunscreens.

Isotretinoin

Similar to retinoids, isotretinoin is also a Vitamin A derivative. This medication is an oral version of a retinoid and is arguably one of the most effective acne treatments to date. Isotretinoin works internally by reducing sebum (oil) production which consequently reduces comedone formation, lowers surface and ductal proliferation of Cutibacterium acnes (bacteria thought to be responsible for causing acne), and reduces the inflammation responsible for the redness and raised bumps during an acne breakout.^[6] While it is a powerful treatment, it does come with its own side effect profile. The most common side effect is skin dryness and irritation due to the decrease in oil production. Rarely a phototoxic (i.e. sunburn-like) reactions in response to solar exposure, which occurs due to the decreased thickness of the stratum corneum.^[1,2]

The original brand name of isotretinoin is known as Accutane^®, but there are now many other brand versions on the market, such as Absorica^®, Amnesteem^®, Claravis^®, Myorisan^®, Sotret^®, and Zenatane^™.^[7]

Alpha hydroxy acids (AHA) and beta hydroxy acids (BHA)

Alpha and Beta Hydroxy Acids are commonly used ingredients in skin care products that exfoliate and peel the skin. These acids functions are very similar but differ in their chemical structure. The structural difference affects their solubility. Beta Hydroxy Acids (BHAs), such as salicylic acid, are lipid soluble. This characteristic allows for the product to penetrate deep into the acne causing sebaceous (oil) follicles, making this acid appropriate for comedones and oily skin.^[8] In contrast, Alpha Hydroxy Acids (AHA) are water soluble and do not affect sebaceous glands. Glycolic acid, lactic acid, and malic acid are commonly used AHA’s in acne, and function to exfoliate epidermal cells of the stratum corneum.^[8] Exfoliation serves to gently remove the buildup of dead cells on the skin surface that can contribute to clogged pores and follicles. Both of these acids function by sloughing off the outer layer of the skin. The removal of the protective skin barrier increases solar skin sensitivity.^[9]

Benzoyl peroxide (BPO)

Benzoyl peroxide is a powerful oxidizing agent that has been effectively used for over five decades to treat acne. BPO can be found in many various acne specific face washes, gels, creams, lotions, toners, and spot treatments. This powerful antiseptic is directly toxic to C. acnes, the bacteria responsible for causing acne.^[10] In addition to killing the bacteria, it also helps to reduce both acne lesions and the oil on the skin, making this agent a very popular acne therapy.^[10] One of the side effects of BPO is skin dryness. This dryness can make the skin more irritated and sensitive, specifically to the sun.

BPO is found in many over the counter acne treatments, as well as prescribed therapies. To avoid a photosensitive reaction, it is important to check labels on products purchased over the counter. Commonly prescribed medications containing BPO include:

• Onexton^® (benzoyl peroxide/ clindamycin topical)
• Acanya^® (benzoyl peroxide/ clindamycin topical)
• Benzac^® (benzoyl peroxide topical)
• Benzaclin^® (benzoyl peroxide/ clindamycin topical)
• Duac^® (benzoyl peroxide/ clindamycin topical)
• Epiduo^® (adapalene/ benzoyl peroxide topical)
• Epiduo-Forte^® (adapalene/ benzoyl peroxide topical)
• Onexton^® (benzoyl peroxide/ clindamycin topical)

Antibiotics

The main effect of antibiotics as an acne treatment is due to their effect on reducing inflammation. These agents also help to reduce the number of the bacteria C. acnes – a common skin bacteria that is associated with acne. This is another common and effective treatment for many people. Antibiotics for the treatment of acne come in both oral and topical formulations. While both options are effective, some of the oral antibiotics commonly prescribed for acne have been shown to increase skin sensitivity at high doses.^[2]

Antibiotic-induced photosensitivity is overall uncommon but when it occurs, it is by far more common with the use of doxycycline.^[11,12] Skin reactions are a result of a phototoxic reaction, manifesting as an exaggerated sunburn after immediate exposure. Doxycycline can also induce a phototoxic reaction that can result in a breakdown of the nails.

Acne treatment procedures

Acne medications are not the only offenders in inducing photosensitivity. Various acne specific procedures are also associated with causing an increase in sun sensitivity. Many acne procedures target the removal of the outer layer of the skin. By removing this protective skin layer, these treatments also remove some of the skin’s natural deference against harmful UV rays. Acne procedures that can cause an increase in sun sensitivity are, microdermabrasion, and chemical peels.^[13,14]

Laser procedures are another popular treatment for acne scar removal. However, studies have shown that concurrent treatment with a known photosensitive provoking medication can initiate a similar reaction in response to the laser therapy.^[15] The risk of developing a phototoxic reaction after laser therapy while on an antibiotic medication will depend significantly on the type of medication and type of laser. Therefore, before your laser treatment, it is important to tell the dermatologist if you are taking any medication.

Preventing Photosensitivity

• Avoid overexposure to the sun
• Wear sun protective clothing
• Wear broad-spectrum sunscreen of at least SPF 50 and reapply
• Consult your dermatologist if you believe that a medication has led to a photosensitive reaction
• Consult a dermatologist if you are unsure about which medications can cause reactions

Practical Strategies for Medication Use

A good strategy to minimize irritation as a result of acne medications is to start low and go slow. If beginning a new topical therapy, such as a retinoid, starting off by applying a small pea-sized amount to the face every other night can help reduce skin irritation. This will also allow the skin time to acclimate to the new medication. As tolerance develops, increasing the frequency of application to every night is appropriate. Additionally, diluting the medication with moisturizer or applying moisturizer after application may also help to reduce irritation and dryness associated with the medication.