Why is my daughter experiencing extreme pain and heavy bleeding during her period?

This is not rare among young women and often responds to medication started before the anticipated menses. When simple meds fail this is one of many conditions where well dose hormonals (BC Pills) might be helpful in reducing symptoms. An evaluation by her doc or an OBGYN would be helpful.

Agree with Dr. Ferguson. Her doctor can prescribe medication that would limit her periods to once a year or so. She could go off the medication when she is ready to have children She should take iron and multivitamin supplements to prevent anemia.