Hi! Start by following a good diet - Eat adequate amount of protein. Your hair is made up mainly of proteins. Include skimmed milk, cottage cheese, lentils in diet. Vitamin C, Zinc and Vitamin B are other important nutrients for great hair health. So include lot of fresh fruits, vegetables and whole grains in your daily diet.
Next important step is to follow good hair care - Oiling your hair with a mixture of oils like olive, sesame, coconut and castor oil keeps provides moisture to your hair and prevent them from drying and breakage.
See a Dermatologist for medications.
Avoid random medications