Table 1.

Summary of current recommendation for nonbiologic and biologic systemic medications in AD treatment.

Treatment	Mechanism of action	Recommendation
Systemic corticosteroids	Non-biologic, conventional systemic broad-spectrum immunosuppressive therapy.	•Without confirmed COVID-19 infection: effect on severity of COVID-19 is still unknown. Taper to lowest effective dose (1–3, 17). •With confirmed COVID-19 infection: treatment should be discontinued because it can increase the risk of infections (1, 2, 18). •Caution regarding initiation and dupilumab is preferred in such cases (1, 2, 17).
Dupilumab	Biological therapy. It blocks the IL-4/IL-13 receptor chain which inhibits Th2 inflammation. It does not impair the immune host response against viral infections.	•Without confirmed COVID-19 infection: treatment continued and might be preferred in selected severe cases than conventional treatment since it is not considered to increase the risk for viral infections (1–3, 17, 18). •With confirmed COVID-19 infection: treatment should be stopped for a minimum of 2 weeks until recovery and/ or a documented negative swab analysis for SARS-Cov-2 (2, 3, 17, 18). •Patient can be initiated safely on this regimen (1, 2, 17).
Methotrexate	Non-biologic, conventional systemic immunosuppressive therapy. It inhibits the synthesis of nitrogenous bases leading to a halt in the proliferation of T and B lymphocytes.	•Without confirmed COVID-19 infection: effect on severity of COVID-19 is still unknown. Taper to lowest effective dose (1–3, 17). •With confirmed COVID-19 infection: treatment should be discontinued because it can increase the risk of infections (2, 3, 17). •Caution regarding initiation and dupilumab is preferred in such cases (1, 2, 17).
Cyclosporine	Non-biologic, conventional systemic immunosuppressive therapy. It is a calcineurin inhibitor which will inhibit TCR signaling and therefore inhibits the activation of T helper lymphocytes.	•Without confirmed COVID-19 infection: effect on severity of COVID-19 is still unknown. Taper to lowest effective dose (1–3, 17). •With confirmed COVID-19 infection: treatment should be discontinued because it can increase the risk of infections (2, 3, 17). •Caution regarding initiation and dupilumab is preferred in such cases (1, 2, 17).
Azathioprine	Nonbiologic, conventional systemic immunosuppressive therapy. It inhibits T and B lymphocyte proliferation.	•Without confirmed COVID-19 infection: effect on severity of COVID-19 is still unknown with no data on its safety profile. Taper to lowest effective dose (1–3, 17). •With confirmed COVID-19 infection: treatment should be discontinued because it can increase the risk of infections (2, 3, 17). •Caution regarding initiation and dupilumab is preferred in such cases (1, 2, 17).
JAK inhibitors	Biological therapy. It inhibits the ATP-binding site of JAK thus inhibiting the enzyme's activity and suppressing subsequent signal transduction.	•Without confirmed COVID-19 infection: treatment can be continued (2). •With confirmed COVID-19 infection: discontinuation during initial infection. However, a potential treatment role for inhibiting the cytokine release is under investigation (2). •No clear data about safety of initiating therapy
Phototherapy	Non-biological therapy.	Discontinued to limit patient's exposure (1, 3).

If systemic therapy needs to be discontinued, the clinician should focus on maximizing the use of natural sunlight, bleach baths, moisturizers, topical therapies, and wet wraps to maintain disease control (1–3, 17).