Trusted sources
Official references
Use primary sources and licensed clinicians for medication decisions — not blog calculators.
DailyMed (U.S. drug labels)
Official FDA labeling for many U.S. prescription and OTC products.
FDA Drugs
Drug safety communications, approvals, and consumer resources.
MedlinePlus
Plain-language health topics from the U.S. National Library of Medicine.
CDC
Public health guidance, prevention topics, and vaccine information.
Find a pharmacist / local pharmacy
When in doubt about a medicine you already take, ask a pharmacist or your clinician directly.