According to the Mylan website, Mylan 146 matches up to
Spironolactone 25 mg(old appearance) BUT on the website, the reverse side of the pill is blank??
You can take a look by searching for MYLAN146 at
http://www.mylan.com/product_guide/search/
You can phone Mylan Pharmaceuticals at 1-877-4INFO-RX / (1-877-446-3679) to confirm.
Info at
http://spironolactone.drugs.com