I had few weeks back said to sis Acacia regarding not treating cold for 3 days, here's the reference from Mustadrak Al Hakim via 5 Minute Madrasah, note that it actually says 'for a few days' - also I'll come to the 3 days part, I have to read further into the book or ask Ulamah as there are hundreds of ahadith's in the book, the book itself is about 826 pages, also I can't seem to find Mustadrak Al Hakim in English, so please wait for it, right now, its in Urdu.
Its related from the Mother of the Believers, Hadrath Ayesha رضي الله عنه, Hadith # 8262, in 5 minute madrasah, Pg # 322. Urdu page view: archive.org/stream/SirfPanchMinuteKaMadrasah#page/n0/mode...
Note: If anyone has link for Mustadrak Al Hakim in English, please share.
والسلام




