Drug prescriptions - Generic substitutions
If you get a prescription for a particular drug from your doctor, you must have him/her sign “Dispense as Written” on the prescription. This is due to the Generic Drug act amendment in 1990.
http://www.attorneygeneral.gov/pei/know/generic.cfm
It is interesting that the law allows the Pharmacist to substitute the prescribed drug on your prescription with a Generic brand without consulting you first. However, you as a consumer cannot chose to substitute your prescribed drug with a Generic brand.
On a positive side, you can contest the Generic substitute as long as you are willing to accept the differences in cost. As usual, you are your own advocate.
Alex