Several drug or drug candidates feature amidine substituents. Examples include the antiprotozoal Imidocarb, the  insecticide amitraz , the anthelmintic tribendimidine, and xylamidine, an antagonist at the 5HT2A receptor.
Formamidinium (see below) may be reacted with a metal halide to form the light-absorbing semiconducting material in perovskite solar cells. Formamidinium (FA) cations or halides may partially or fully replace methylammonium halides in forming perovskite absorber layers in photovoltaic devices.