Stomach flu or gastroenteritis infection signs and symptoms include nausea, vomiting, and diarrhea that lasts for about 7-14 days. The stomach flu is spread from person to person, usually via fecal to oral route from poor hand-washing or hygiene techniques.
Location: Egypt. Posts: 1,672. Re: How long for meds to take effect. It takes from 1 to 2 days in order for your high bp meds to work, but it reach its maximum effect in 1 week and some times it takes 2 weeks. They said that but I think it's only a week, not more than that.
Making the world better, one answer at a time. Benadryl, or diphenhydramine hydrochloride, when taken by mouth, works within 15 to 60 minutes. When injected through a muscle, it takes 20 to 30 minutes to work.When injected through a vein, it works rapidly. The effects of diphenhydramine hydrochloride work for approximately 4 to 8 hours, regardless of the form in which it is taken.aking the world better, one answer at a time. Benadryl, or diphenhydramine hydrochloride, when taken by mouth, works within 15 to 60 minutes. When injected through a muscle, it takes 20 to 30 minutes to work. When injected through a vein, it works rapidly.