Aim: to quantify the extent of counterfeit sildenafil in Indonesia.
Methods: the study was conducted in 4 big areas: Jakarta, Bandung, East Java (Surabaya and Malang), and Medan. Sildenafil 100 mg tablets were purchased from pharmacies, drugstores, street peddlers, and 3 Indonesian websites. The outlets were chosen by random sampling in each stratum (type of outlet). Sildenafil tablets purchased were sent to Pfizer Quality Operations Division, Dalian, China, for authenticity evaluations (by infra red spectral analysis). All counterfeit tablets were then sent to Pfizer Counterfeit Medicines Laboratory, Sandwich, UK, a portion of which were analyzed quantitatively for sildenafil concentration per tablet (by HPLC).
Results: a total of 518 sildenafil 100 mg tablets were collected and sent to Dalian. Of these tablets, 284 tablets (55%) were genuine sildenafil and 234 tablets (45%) were counterfeit sildenafil. Counterfeit sildenafil were mostly found in street peddlers (100%), in drugstores (56%), and from internet (33%), but pharmacies also had (13%) counterfeit sildenafil. The sildenafil content of 106 counterfeit tablets analyzed varied from 24 to 157 mg per 100 mg tablet. No analysis was done to determine other active ingredient.
Conclusion: 45% sildenafil 100 mg tablets in Indonesia were found counterfeit and widely distributed in street peddlers, drugstores, and pharmacies. This report is aimed to alert the potential consumers, health professionals and regulators of this problem.