I am 48, I have hyper tension, my doctor advised me to take Norvasc 5 mg tablets, but I was having problem with the use of the medicine, the doctor changed medicine from Norvasc 5mg tablets to sofvasc 5mg (Wilson company ) tablets, both tablets have the same salt i.e. Amolodipine Besylate, please let me know the difference between the two, when they are having the same salt