Drugs can be quite useful for disease states other than what they were developed for. Sildenafil was developed to treat pulmonary hypertension which can affect the lungs and the heart. It never got off the ground and development was close to being abandoned, but Pfizer did make a couple of bucks when it marketed sildenafil as Viagra after some anecdotal effects arose.
It is not always known how drugs work either .
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3990949/ In 1963 an even more potent benzodiazepine, diazepam 1 (Valium), was released to the public, possessing “a greater dissociation between its sedative and anxiolytic properties.”2 Not only prescribed for anxiety, diazepam had therapeutic benefits for epilepsy, muscle spasms, and alcohol withdrawal.3 Diazepam quickly became one of the top selling drugs of all time, despite 15 years without significant knowledge of its mechanism of action.
Re azithromycin,
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7290142/It has been shown that AZM has significant antiviral properties. In contrast with CQ or HCQ, its antiviral activity has been shown in vitro and/or in vivo on a large panel of viruses: Ebola, Zika, respiratory syncytial virus, influenzae H1N1 virus, enterovirus, and rhinovirus [4–13].
Re zinc,
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7247509/Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents the largest current health challenge for the society. At the moment, the therapeutic strategies to deal with this disease are only supportive. It is well known that zinc (Zn) possesses a variety of direct and indirect antiviral properties, which are realized through different mechanisms. Administration of Zn supplement has a potential to enhance antiviral immunity, both innate and humoral, and to restore depleted immune cell function or to improve normal immune cell function, in particular in immunocompromised or elderly patients. Zn may also act in a synergistic manner when co-administered with the standard antiviral therapy, as was demonstrated in patients with hepatitis C, HIV, and SARS-CoV-1.
I'll reserve judgement for now, but Orange man bad. Big Pharma good.