Acne Vulgaris: A Guide to Diagnosis, Treatment, and Management

I think it’s acne; how do I diagnose it for sure?

High clinical suspicion as well as documented improvement with acne treatment help confirm the diagnosis. Biopsies and invasive procedures in general are not necessary unless diagnostic uncertainty exists. Lack of improvement with treatment should warrant re-evaluation of the diagnosis. (Al-Natour, 2012) Look for risk factors for acne production, such as using face products that occlude the pores, medications (see below), increased reported stress, dietary changes (with high glycemic indices), smoking exposure, occupational hazards (high sweat production with tight-fitting clothes), and obesity. For the primary care providers out there, ensure that you have ruled out Cushing syndrome in the right clinical setting. Furthermore, in women, hyperandrogenism suggestive of polycystic ovarian syndrome may present as a woman concerned about acne (typically, they will have concurrent hirsutism and menstrual irregularities). (Oon, et al., 2019)

When it comes to treating acne vulgaris, where do I start?

Before initiating treatment, we need to make sure the acne is not caused by a medication or supplement that the patient is taking, known as drug-induced acne. (Kazandjieva Jana, 2017) (Al-Natour, 2012) Be suspicious when your patient presents with sudden onset eruptions at an older age (older than 25 years), appearing on the face or neck or unusual locations in the setting of recent new medication use that is resistant to typical acne treatments. A helpful distinction is that patients with drug-induced acne will not have comedones and will complain of pruritus. (Al-Natour, 2012) In women, common culprits include hormonal contraceptives. In all genders, be aware of these medications that can cause acne: steroids, lithium, and TNF-alpha inhibitors, among others.  (Kazandjieva Jana, 2017)

For the most part, first-line acne treatments have not changed in the past few years; however, there are a plethora of adjunctive treatments now available. Acne treatment is based on severity and type. For the purposes of this article, we are assuming you have made a diagnosis of acne vulgaris.

When initiating treatment, it’s important to be able to characterize the severity of the disease. Characterized as either mild, moderate, or severe, the grading system does vary based on what clinical trial you are referencing; however, without delving into the minutia, in general, quantitative measurements looking at lesion counts and the types of lesions help determine the severity of disease. By grading the disease severity, you can then determine how aggressive you want to be with treatment. For example, the comprehensive acne severity scale (CASS) grades the severity of acne from 0-5, with 0 representing clear skin with no or barely noticeable comedones and papules and 5 representing very severe, highly inflammatory acne (see Table below).

In general, no matter the severity, if using a topical medication, cream and other non-alcohol-based types are advised for better absorption.

Grade 0-2 acne can be treated with topical therapies such as antimicrobial agents targeting P acnes. Monotherapy is not advised, given both the increasing prevalence of antibiotic resistance as well as decreased effectiveness compared to combination therapy.

Alternatives to topical antimicrobials include benzoyl peroxide, salicylic acid, dermocosmetics, and topical retinoids. Benzoyl peroxide is available over the counter and comes in different formulations; 2.5%-5% are the most commonly prescribed; 10% is likely to cause irritation without much benefit. (Usatine, Bambekova, & Shiu) Topical retinoids include tretinoin (Retin-A; gel, cream, liquid), adapalene gel (Differin), and tazarotene (Tazarac 0.1%). Adapalene is less irritating than tretinoin and is available over the counter (which would be beneficial in our patient without insurance). While tazarotene is the strongest of the retinoids, it also is the most associated with irritation, which may limit patient compliance. Retinoids are utilized with either comedonal or inflammatory acne as well as in maintenance for treated acne. Azelaic acid is helpful in treating postinflammatory hyperpigmentation. (Usatine, Bambekova, & Shiu)

If topical therapy is not enough, oral medications can be considered; however, they should never be used in combination. Oral antibiotics, such as doxycycline 100-200 mg/d, tetracyline 500-1000 mg/d, and erythromycin 250-500 mg/twice a day, are considered first line. Bactrim double strength has also been used previously; however, its association with Stevens-Johnson syndrome has limited its use, as safer alternative antibiotics exist. Typically, antibiotics require at least 6 weeks before effects are seen but are not prescribed for longer than 3-4 months at a time. If a pulse style of prescribing is desired, azithromycin can be considered, as it has not been found to be inferior to longer course doxycycline. Azithromycin is commonly prescribed at 500 mg daily for 4 days each month. (Parsad D, 2001) (Naieni FF, 2006) This is a great option if patient compliance is a concern, and the pulse dose cost is less than longer term antibiotic regimens. Those who are pregnant can safely take erythromycin but should avoid this if they have concurrent seizure or bipolar disorder (on carbamazepine). Doxycycline is a good option in patients with chronic kidney disease but not in those who have dysphagia or burn easily with sun exposure. Avoid tetracycline if renal or liver disease is present in your patient.

Women with moderate-to-severe papulopustular acne, hyperandrogenism, or need for contraception, and those already on topical or systemic therapies, may benefit from consideration of combined oral contraceptives. In comparison to the oral antibiotics above, oral contraceptives have similar efficacy in reducing lesions after 6 months of treatment. Given the limited duration of treatment with antibiotics, patients requesting a prolonged treatment option may benefit from contraceptives. Medications containing levonorgestrel (Microgynon) and drospirenone (Yaz, Yasmin) have been found to be effective in both inflammatory and noninflammatory acne. Those containing cyproterone may not be more effective than those without. Typically starting on the first day of the menstrual cycle, patients will take the medication for 21 days straight, with a 7-day free period, then repeat this cycle for 6-12 months. As with any oral contraceptive, avoid prescribing in women who smoke, are postpartum, have uncontrolled hypertension, have history of deep venous thromboses or pulmonary emboli, or have migraines with auras, among others.

If severe nodulocystic acne is present and oral antibiotics have failed, or scarring is present, a referral toa dermatologist is advised. Prior to referral, liver function tests and a lipid panel should be checked. These patients may be candidates for systemic isotretinoin. It is typically prescribed in 6-month periods; pulse dosing, while previously done, is no longer utilized. Pregnancy is absolutely contraindicated while on this medication due to the high occurrence of teratogenic events. A pledge application is required for all patients on systemic isotretinoin.

Other than medications, adjunctive treatments such as chemical peels (40% glycolic acid), topical 5-aminolevulinic acid, and phototherapy with blue or red light have been studied with varying success rates. Chemical peels have limited supporting trials in treating moderate acne; more research is advised before I would considering this for your patient. Light treatments involving 5-aminosalicylic acid and phototherapies such as intense pulsed light can help with inflammatory lesions and scarring. Those with alternating red- and blue-light LEDs may decrease inflammatory lesions.

Acne Vulgaris Treatment Classes With Examples

Benzoyl Peroxide

• Benzoyl peroxide 2.5%, 5%, 10%* as lotion, gel, cream, wash
• *10% is not advised, as it has not been found to be any more efficacious than 5%

Retinoids

• Tretinoin 0.025%
• Isotretinoin by mouth 10 mg, 40 mg
• Adapalene 0.1%
• Alitretinoin 0.1%
• Tazarotene 0.05%, 0.1%

Topical Antibiotics

• 1% / 2% clindamycin
• 1% / 2% / 3% erythromycin
• 5% / 7% dapsone

Oral Antibiotics

• Doxycycline 50 mg / 100 mg daily or twice a day
• Tetracycline 500-1000 mg / day
• Erythromycin 500 mg twice a day

Commonly Studied Acne Vulgaris Treatment Combinations (Gold, 2010)

Benzoyl Peroxide plus Retinoid

• Epiduo® gel (benzoyl peroxide + adapalene)

Benzoyl Peroxide plus Topical Antibiotic

• Duac® or BenzaClin (benzoyl peroxide 5% plus clindamycin 1%)
• Benzoyl peroxide 2.5% plus adapalene 0.1% (may be better tolerated than benzoyl peroxide 5%)
• Benzamycin (benzoyl peroxide 5% plus erythromycin 3%)

Topical Antibiotic plus Retinoid

• Clindamycin 1% plus tretinoin 0.025%
• Clindamycin 1% plus adapalene gel 0.1%
• Erythromycin 4% plus tretinoin 0.025%