I suffer from excessive hair loss till 1year i can't use any kind of medicine till....i only do some exercise and yoga to prevent this hair fall .....there is no results..... can anyone suggest me any kinds of medicine to prevent hair fall problem?

Depends on cause...: One's primary care doctor can check for medical causes. If none are found, then one can see a dermatologist, especially one specializing in hair restoration (some treatments: minoxidil, etc, ...). Medical causes may include: hormonal problems (low thyroid), seborrhea, alopecia areata, stressful illness. Other causes: genetic male or female pattern baldness, telogen effluvium, etc...