Consideration of immunomodulatory actions of morphine in COVID-19 - Short report.

Cytokine storm in COVID-19 is linked to disease severity and mortality. 40% of patients with severe COVID-19 require mechanical ventilation. Analgesia and sedation are used for treatment of pain, facilitation of mechanical ventilation, or management of acute agitation. Herein, we present the immunomodulating actions of morphine that may either improve or worsen the clinical course of COVID-19 once cytokine storm develops. A literature search was performed to find articles on potential immunomodulatory effects of morphine. Taken together, the results of in vitro and in vivo models in non-COVID-19 conditions suggest that morphine could have a beneficial effect by mitigating the cytokine storm in the early stages of severe COVID-19. In contrast, it could be potentially harmful in late stages of severe COVID-19, especially in the presence of septic shock.