Drug Usage Statistics, United States, 2013 - 2020
Diphenhydramine; Summary for 2020
|Top drug rank
|Estimated number of prescriptions in the United States (2020)
|Estimated number of patients in the United States (2020)
|Average total drug cost (USD)
|Per day of therapy
|Average out-of-pocket cost (USD)
|Per day of therapy
Total Prescriptions and Patients Per Year (2013 - 2020)
Rank of Top Drugs Over Time
"Rank" refers to the frequency that a given medication is prescribed within a calendar year compared to all other medications. A rank of "4" would indicate that the medication was the fourth most commonly prescribed medication.
Drug Cost Over Time (2013 - 2020)
- Cost Per Prescription Fill: Average cost per filled prescription regardless of how many days of therapy the prescription is filled for (e.g. 10 days, 30 days, 90 days, etc.)
- Cost per Day of Therapy: The average cost per prescription fill divided by the days of therapy. For example, a 10-day antibiotic course costing $30 would be $3 per day. Similarly, a 30-day supply of an oral antihypetensive costing $30 would be $1 per day.
- Total cost: The average total cost of the medication including the out-of-pocket cost (see below) plus the amount paid by other parties (Medicare, Medicaid, private insurance, Veterans Administration, TRICARE, other state/federal sources, Worker's compensation, and other miscellaneous sources)
- Out-of-pocket cost: The average payment made by the patient which may include deductibles, coinsurance, copayments, or the cash price paid without insurance coverage.
Cost Per Prescription Fill (USD)
Cost Per Day of Therapy (USD/day)
Distribution of Dispensed Dosage Forms (2020)
No data available
Distribution of Days Supplied (2020)
"Days supply" is defined as the number of days that a prescription should last. For example, a prescription of 60 tablets that is taken twice daily has a day supply of 30 days.
Drug synonyms are used during the sanitation and standardization process of "cleaning" the original data source (MEPS). Occassionally, brand names may be listed below that are no longer on the market or are very infrequently used.
Brand Name Synonyms
Generic Drug Synonyms and Salts
- Diphenhydramine Hydrochloride; Zinc Acetate Anhydrous
FDA Approval Information
|Established Pharmacologic Class (EPC): ||N/A
|Initial FDA approval date: ||
|First FDA applicant: ||
|First dosage form: ||
Prescription data source: Medical Expenditure Panel Survey (MEPS) 2013-2020. Agency for Healthcare Research and Quality (AHRQ), Rockville, MD. ClinCalc DrugStats Database version 2022.08. Read more about the ClinCalc DrugStats database.
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