From the Guidelines
For a moderate pool-related rash not responding to Benadryl, I recommend a topical corticosteroid such as triamcinolone 0.1% cream applied thinly to affected areas twice daily for 7-10 days, as this approach is supported by the most recent and highest quality study available 1. When considering treatment options, it's essential to prioritize reducing inflammation and immune response to the irritant.
- Prescription oral antihistamines like cetirizine (10mg daily) or loratadine (10mg daily) may be more effective than Benadryl and cause less drowsiness.
- For more severe cases, a short course of oral prednisone might be necessary, typically 20-40mg daily for 5 days with a taper, as suggested by recent guidelines 1. The rash could be contact dermatitis from pool chemicals like chlorine or bromine, or possibly "hot tub folliculitis" if small pustules are present, which might require topical clindamycin 1% solution.
- Keeping the affected area clean and dry is important, and avoiding further pool exposure until the rash resolves.
- If the rash worsens, spreads, or shows signs of infection (increasing pain, warmth, pus, or fever), prompt medical reevaluation is necessary, considering the potential for severe skin reactions as outlined in recent studies 1. It's also worth noting that oral antibiotics for 6 weeks at the start of therapy with or without topical low/moderate strength steroid to face and chest twice daily may be beneficial in certain cases, as indicated by recent research 1.
From the Research
Possible Prescription Options
For a patient with a moderate rash acquired from a pool who is not responding to Benadryl (diphenhydramine), the following prescription options may be considered:
- Topical corticosteroids, which are effective in treating inflammatory skin diseases such as atopic dermatitis 2, 3, 4, 5
- Topical calcineurin inhibitors, such as pimecrolimus and tacrolimus, which can be used in conjunction with topical corticosteroids as first-line treatment for atopic dermatitis 3
- Ultraviolet phototherapy, which is a safe and effective treatment for moderate to severe atopic dermatitis when first-line treatments are not adequate 3
- Antistaphylococcal antibiotics, which are effective in treating secondary skin infections 3
- Newer medications, such as crisaborole and dupilumab, which are effective in treating atopic dermatitis but may be cost-prohibitive for most patients 3
Considerations for Topical Corticosteroid Use
When prescribing topical corticosteroids, the following considerations should be taken into account:
- The risk of adverse effects, such as atrophy, striae, rosacea, telangiectasias, purpura, and other cutaneous and systemic reactions, which increases with prolonged use, large area of application, higher potency, occlusion, and application to areas of thinner skin 2, 5
- The potential for contact allergy to topical corticosteroids, which can lead to systemic contact dermatitis 6
- The importance of correct patient application, which is critical to successful use, and can be taught using the fingertip unit method 5