I have been taking amitriptyline for a couple of years very successfully. Those pills were imprinted with GG 431 - sandoz pharmeceuticals, inc.

Recently, my prescription came imprinted V 2103 - qualitest pharmeceuticals, inc. - which doesn't work anywhere near as well.

Are there any reports or information, even anecdotal, that the quality of the amitriptyline from the 2 above manufacturers is significantly different?