Reference
Where these four drugs came from
These molecules have addresses. Below are the laboratories that produced them and the agencies that later decided how they could be sold.
Schering Corporation (historic)
2000 Galloping Hill Road, Kenilworth, NJ 07033, USA
Where Arthur Nobile's microbial-oxidation work turned cortisone into prednisone and prednisolone in the mid-1950s - the leap that gave medicine a potent oral corticosteroid.
The Upjohn Company (historic)
7000 Portage Road, Kalamazoo, MI 49001, USA
The Michigan manufacturer that marketed prednisone under the Deltasone brand, one of the names by which generations of patients came to know the drug.
Former Pfizer Discovery Laboratories
Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
The Kent site where sildenafil (UK-92,480) was first trialled for angina, before an unexpected side effect redirected the entire programme toward erectile dysfunction.
ICOS Corporation (historic)
22021 20th Avenue SE, Bothell, WA 98021, USA
The Washington biotech that discovered tadalafil and partnered with Eli Lilly to bring the long-acting PDE5 inhibitor to market as Cialis.
Bayer AG (Wuppertal)
Aprather Weg 18a, 42113 Wuppertal, Germany
The German laboratories behind vardenafil, later sold as Levitra and as the orodispersible Staxyn tablet.
U.S. Food and Drug Administration
10903 New Hampshire Avenue, Silver Spring, MD 20993, USA
The regulator whose prescribing information and safety communications anchor the doses, warnings and interaction rules quoted across this site.
European Medicines Agency
Domenico Scarlattilaan 6, 1083 HS Amsterdam, Netherlands
The European authority whose assessments and pharmacovigilance work shape how these medicines are labelled and used across the EU.
American College of Rheumatology
2200 Lake Boulevard NE, Atlanta, GA 30319, USA
Keeper of the glucocorticoid-management guidance on bone protection, tapering and monitoring that informs how a prednisone course should be run and wound down.
Why the origin still matters on the page
A steroid derived from cortisone chemistry explains both what 2.5 mg is good for and the bone and blood-sugar bill that a long course runs up. A failed angina trial in Kent explains why sildenafil is still timed around a meal and still absolutely barred with nitrates. Small differences in how each compound treats the phosphodiesterase family explain why one has a window measured in days, one is governed by dinner, and one carries a note about cardiac rhythm. Each profile links back to the laboratory that shaped the drug.