What treatment is recommended for a persistent rash after 10 days of prednisone (40mg) and a completed azithromycin (Z-pack) course, following exposure to a stray cat and/or poison ivy?

From the Guidelines

For a persistent rash that hasn't responded to 10 days of prednisone (40mg) and a completed azithromycin course following exposure to a stray cat and/or poison ivy, I strongly recommend seeking in-person medical evaluation. This situation requires professional assessment as it could be cat scratch disease (from Bartonella henselae bacteria) or severe contact dermatitis that needs different treatment. The initial treatment with prednisone and azithromycin may not have been sufficient or appropriate for the underlying condition, considering the lack of response. According to the 2024 American Heart Association and American Red Cross guidelines for first aid 1, washing the exposed area with soap and water as soon as possible after exposure to poison ivy, oak, or sumac is recommended, but the usefulness of over-the-counter topical steroids and antihistamines for alleviating local symptoms is uncertain.

Given the persistence of the rash despite initial treatment, it's crucial to consider other management options. Cool compresses 1 and oatmeal baths 1 may be considered for relief of local symptoms from exposure to poison ivy, oak, or sumac, but these measures alone may not be sufficient for a rash that has persisted for several weeks. The failure of high-dose prednisone and azithromycin indicates this isn't a simple case, and laboratory testing or skin biopsy may be necessary to determine the exact cause and appropriate treatment. Cat scratch disease typically requires longer antibiotic courses, while severe poison ivy may need topical steroids, oral steroids for a longer duration, or even steroid injections.

Some key considerations for the in-person medical evaluation include:

• Detailed history of the exposure and symptoms
• Physical examination of the rash and any other affected areas
• Potential laboratory tests to rule out infections such as cat scratch disease
• Consideration of alternative treatments based on the diagnosis, such as extended antibiotic courses for cat scratch disease or adjusted steroid regimens for severe contact dermatitis. While waiting for an appointment, continuing any prescribed antihistamines and applying cool compresses to relieve symptoms can be beneficial. However, a thorough medical evaluation is essential to guide further treatment and prevent potential complications.

From the FDA Drug Label

If after a reasonable period of time there is a lack of satisfactory clinical response, prednisone should be discontinued and the patient transferred to other appropriate therapy.

The patient has already completed 10 days of prednisone (40mg) and a Z-pack course, and the rash still persists after another week.

• The lack of satisfactory clinical response to the initial treatment suggests that prednisone should be discontinued.
• The patient should be transferred to other appropriate therapy, but the FDA drug label does not specify what this therapy should be for a persistent rash after exposure to a stray cat and/or poison ivy 2.

From the Research

Treatment Options for Persistent Rash

The user has been taking prednisone (40mg) for 10 days and has completed a course of azithromycin (Z-pack) after coming into contact with a stray cat and/or poison ivy, but the rash still persists after another week.

• The treatment for severe poison ivy contact dermatitis was examined in a study 3, which compared the efficacy of a 5-day regimen of 40 mg oral prednisone daily to the same 5-day regimen followed by a prednisone taper over a total of 15 days. The study found that patients receiving the long course regimen were significantly less likely to utilize other medications.
• Another study 4 found that a short course of oral prednisone was effective in inducing remission in nearly 50% of patients with antihistamine-resistant chronic urticaria.
• A study on the outpatient management of acute urticaria 5 found that the addition of a prednisone burst improved the symptomatic and clinical response of acute urticaria to antihistamines.
• There is limited information available on the specific treatment of a persistent rash after 10 days of prednisone and a completed Z-pack course. However, the studies suggest that a longer course of prednisone or a different treatment approach may be necessary.

Possible Next Steps

• Consider consulting a healthcare professional to determine the best course of treatment for the persistent rash.
• The healthcare professional may recommend a longer course of prednisone, a different medication, or other treatment options based on the individual's specific condition and medical history.
• It is essential to follow the healthcare professional's advice and guidance to ensure proper treatment and management of the rash.