Green tea extract (egcg), quercetin, HCQ are all thought to inhibit RNA viruses in similar ways. Quinine will also do the same. Tonic water has about 60 mg quinine (base) in a liter. My guess after some research is that 1 or 2 liters a day may be prophylactic, at least in some cases. 5 to 10 liters a day will contain a more significant dose for a full blown infection.  5 liters tonic water a day plus some green tea extract or quercetin might be enough to sufficiently inhibit the infection if you started on day one of symptoms. Some people are allergic to quinine.  Vit C- at least 5000 if you get sick, up to 15,000 or 20,000 should be safe and might be beneficial.  Vit D 5000 to 10,000 IU a day if youre sick.  Zinc- 50 to 100 mg a day if you are sick but not all at once; it will make you nauseous.  NAC and Famotidine are also being used in trials so it seems they are worth considering and relatively safe. What I have read about Famotidine (pepcid) seems really promising.  If you have antibiotics around the house save them. Doxycycline, tetracycline, Azithromycin, erythromycin, and ciprofloxicin all seem to inhibit the virus. I haven’t checked all the contraindications with these meds, but they will probably fine to take with these other drugs and supplements, double check.