Report Your Side Effects

Regulatory Agencies

Anyone suffering from persistent finasteride side effects is encouraged to report them to the appropriate agency.


Merck & Co., Inc. originally developed Proscar (finasteride 5 mg) and Propecia (finasteride 1 mg), which were approved by the US Food and Drug Administration in 1993 and 1997, respectively. In June 2021, however, Merck spun off its Organon subsidiary as an independent public company, traded under the symbol “OGN.” Founded in the Netherlands in 1923, Organon bills itself as a “global health care company dedicated to making a world of difference for women, their families and the communities they care for.” Among the Merck products Organon acquired in the deal were Proscar and Propecia. To report adverse events for either finasteride product, call the Organon Service Center at (844)674-3200, or email

In addition to agencies like the U.S. Food and Drug Administration and World Health Organization, PFS patients are encouraged to report their persistent side effects to, a global, independent pharmacovigilance organization whose database is used by patients, doctors and pharmacists to research prescription drugs and their side effects, ideally to identify problems early on in the life of a drug.