29-Year-Old Hiker Self-Treats Her Rash With Coconut Oil

Melba Estrella, MD; Ansley Devore; Alan Snyder; Dirk M. Elston, MD


July 06, 2023

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A 29-year-old woman presents with a worsening rash on her left foot (Figure 1). She reports similar symptoms on her right foot (Figure 2) but notes that her left foot has blisters and is more painful. The patient is an avid outdoors enthusiast. Last weekend, she went on a 7-mile hike for the first time this year.

Figure 1.

Figure 2.

The rash started as a small, erythematous, pruritic patch on her left dorsal great toe 3 days ago. Since then, it has developed into an intensely pruritic localized area of bright red swelling and blistering on her adjacent toe and instep. She believes her right foot is starting to follow the same course.

Application of topical coconut oil and neomycin-polymyxin B-bacitracin (Neosporin) over the past 2 days has failed to relieve her symptoms. She says the pain makes it difficult for her to go on her regular evening hikes after work. She is also concerned that she may have "caught something" on her hike last weekend after crossing several streams barefoot to avoid soaking her new boots.

Her medical history is benign other than mild childhood eczema that resolved by adolescence, occasional yeast infections, onychomycosis of the right great toe, and mild seasonal allergies. She takes a combined oral contraceptive daily, uses benzoyl peroxide 10% facial wash, and maintains a strict vegan diet. She denies any fevers or chills.


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