Dietary Supplement Label Database -- is a collaboration between the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) and National Library of Medicine (NLM). The database "...contains the full label contents from a sample of dietary supplement products marketed in the U.S."
All of the following resources (exception: one commercial publisher) are made possible by the U.S. Government including the Food and Drug Administration and the National Library of Medicine.
DailyMed -- provides information about marketed drugs in the United States (includes FDA drug label package inserts).
Davis' Drug Guide -- contains content from the print version of the Davis Drug Guide (commercial publisher: F.A. Davis).
Information for Healthcare Professionals (Drug Information) -- details regarding drug medication guides, labelling, safety, shortages, and more.
PubChem- The National Library of Medicine retired the Drug Information Portal. All information previously offered in the Drug Information Portal is now contained in PubChem.
FDA Drug Safety Podcasts -- the U.S. Food and Drug Administration's Center for Drug Evaluation and Research produces the podcasts to "provide emerging safety information about drugs in conjunction with the release of Public Health Advisories and other drug safety issues."