Acne vs. Perioral Dermatitis
A 16-year-old girl with a 2-year history of acne has been complaining about tiny "pimples" around her nose and mouth. She says they "burn" and that they seem to be getting worse.
This patient does have a history of eczema, but her skin is clear today. She also reports a recent increase in stress. She noticed the bumps appeared shortly after the onset of stress. The patient had a prescription for triamcinolone 0.1% ointment for her eczema and she applied some to the troublesome area for a few days, but the condition only got worse.
Currently, she is washing her face with Cetaphil Antibacterial bar soap twice a day and applying a salicylic acid 2% cream twice a day. She also uses a 5% benzoyl peroxide gel to spot treat as needed, but has been reluctant to apply anything to these lesions because they burn.
Upon exam, her forehead was clear of any comedones or pustules. She did have a few small papules on her upper cheeks, but mostly perioral and perinasal discrete 1- to 2-mm papules on an erythematous base. Her lips were spared.
At first glance, one could easily confuse this presentation of perioral dermatitis with papular acne. But it is a classic distribution of perioral dermatitis. I always think these lesions are "cute and confined," whereas acne is much more angry and widespread. When perioral dermatitis is treated as if it were acne, the condition flares and worsens because many acne preparations are very irritating to perioral dermatitis.
This patient also has perinasal dermatitis, as demonstrated in the photo showing lesions surrounding the nasal creases. Her treatment involved a sulfur 10% face wash twice a day, clindamycin 2% topical solution twice a day and polysporin at bedtime. I opted not to have her apply the polysporin in the morning because the greasy appearance of the ointment would attract more attention to the area she was already feeling self-conscious about. 
I typically like to prescribe tetracycline 500 mg twice a day for 30 days, but she hasn't tolerated the drug well in the past, so I chose Omnicef 300 mg twice a day for 14 days. I offered her the option to continue with her acne regimen on her forehead only (I don't like teenagers to fall behind on their acne adherence). I also instructed her to never apply the triamcinolone cream to her face, since it's very probable that application of this drug made this condition worse.
A 2-week follow-up visit is crucial for emotional support and reassurance because very commonly, this annoying little rash can last 4 to 6 weeks.