Is Taking Primolut Safe And Effective To Stop Vaginal Bleeding?

I live in Malawi and a friend has been having Depo contraceptive injections for one year. Recently she has been experiencing abdominal pains and has had continuous bleeding for about one month. She went to see the local clinic and they have prescribed her Primolut (or Primlout as spelt on prescription?) 3 times a day for 10 days. I understand from looking on google that primolut is anther progesterone contraceptive. My understanding (again from looking on the net) is that Depo is also progesterone only and that estrogen may be needed to the bleeding. I don't trust the local medical advice - please could you confirm whether primolut to help stop the bleeding is a sensible option?