Drug databases contain information about drugs, including dosing, off-label usage, mechanism of action, adverse effects, and pregnancy concerns. Many drug databases also contain IV compatibility checkers, pill ID, and drug interaction tools.
Point of care databases are decision support tools that function similarly to a wikipedia (that you can cite!). They are a mixture of evidence-based information and expert opinion, written by experts in the field of the article. Clinical topics range from diagnosis and treatment of certain conditions to prevention, to patient information, to an array of medical calculators.
DDx tools are aids to creating differential diagnosis.
Trying to CITE one of these databases? Please visit the APA guide section on citing point of care and drug databases.