Generally, it takes between seven and 10 hours for a dog to digest food, but the many variables mean that only your vet can tell you how long it should be taking.
But how many days after Provera will your period start? When using Provera for amenorrhea (absence of menstrual periods) or abnormal vaginal bleeding, the medication is taken for 5 to 10 days. Menstrual-like vaginal bleeding usually occurs three to seven days after treatment ends.
Each injection gives you protection against pregnancy for 12 weeks. When you have the Depo-Provera injection within the first five days of your menstrual cycle, it works 24hrs after the injection. When you have the Depo-Provera injection after the first five days of your menstrual cycle, it works after 14 days. When the Depo-Provera injection is given to a woman after she has given birth, or had a miscarriage or an abortion, it works immediately. You can get Depo-Provera from your health care provider.