Table 1.

Beneficial effects of testosterone in COVID-19.

References	Study type	Findings
Margue et al. (Marques et al., 2020)	Experimental study	Testosterone improves oxygenation and attenuates tissue hypoxia.
Wang et al. (2021)	Experimental study	Testosterone therapy reduces lung inflammation and fibrosis.
Bianch (Sun et al., 2020)	Systematic review	Testosterone inhibits the synthesis and release of IL-6.
Chen et al. (2020)	Experimental study	Testosterone therapy inhibits NLRP3 inflammasome.
Vignozzi et al. (2012)	Prospective study	Testosterone suppresses NF-κB signaling.
Cayan et al. (Çayan et al., 2020)	Cohort study	Testosterone serum levels are reduced and correlated with COVID-19 severity and mortality.
Rastrelli et al. (2020)	Cohort study	Testosterone serum level is negatively correlated with inflammatory risk factors
Schroder et al. (Rastrelli et al., 2020)	Cohort study	70% of COVID-19 patients have low testosterone at the time of admission.
Cinislioglu et al. (2021)	Prospective study	Testosterone levels are reduced in COVID-19 patients and linked to poor clinical outcomes.
Okcelik et al. (Okçelik, 2021)	Retrospective study	Low testosterone level is connected with COVID-19 severity and risk of death.
Hota et al. (Hotta et al., 2019)	Systematic review	Testosterone supplementation improves endothelial function.
Marin et al. (2010)	In vitro study	Testosterone inhibits oxidative stress.
Bereshchenko et al. (2018)	Systematic review	Testosterone inhibits release of pro-inflammatory and inflammatory cytokines from immune cells.