ABSTRACT
Since Pfizer introduced (1998) Viagra® tablets for erectile disfunction, this medicine has been counterfeited and imitated. Counterfeits of Viagra are tablets intentionally manufactured to look like Viagra, but these tablets may contain wrong ingredients or a wrong active substance or no active substance at all. Imitations of Viagra are also manufactured; these tablets do not look like Viagra, but claim or suggest to contain the same active pharmaceutical ingredient of Viagra, sildenafil citrate. Production and distribution of counterfeits and imitations are of great risk for human health [1,6]. Another problem arises with imitation tablets produced in Asia. India and China do not recognize the European patent law, and therefore legally manufactured products such as Kamagra and Edegra are illegal in the Netherlands.
