What Causes Heavy Vaginal Discharge During Menstruation?

hello,i m rashmi from mumbai.i m 43 years.i have a problem of heavy bleeding monthly 2 days.doctor has suggested me harmonce.i had taken a harmonce about 8 years ago in 2002 for 4 months for having a same problem.so can i take harmonce again now?what r the side effects?thank u.