Hi welcome to HCM
AS IS NORM IN ALLOPATHIC WORLD it is not safe to discontinue abruptly the medicine which you have been taking for years together . yes you can do it gradually . For present problems as falling hair , may be due to other factors like lacking proper nutrition in her diet and lack of activity level and age factor can't be ruled out .
Intake of proper proper nutrition vitamins minerals
antioxidants in natural form and almonds ginger garlic , amla and sufficient hydration also Pranayam - deep breathing ,Bhramary , Kapalbhati ,
yoga ,
meditation and proper rest & sleep and
massage with almond oil in head may make a difference .
In my opinion , by following above regime , gradually giving up the medicine will not be a problem .
Better option is to consult your doctor widely
Or you can consult another doctor for
second opinion for giving up .
Hope this helps solve your query .
Take care . All the best .