Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

Volume 17, Number 9—September 2011


Estimating Effect of Antiviral Drug Use during Pandemic (H1N1) 2009 Outbreak, United States

Charisma Y. Atkins, Anita Patel, Thomas H. Taylor, Matthew Biggerstaff, Toby L. Merlin, Stephanie M. Dulin, Benjamin A. Erickson, Rebekah H. Borse, Robert Hunkler, and Martin I. Meltzer
Author affiliations: Author affiliations: Author affiliations: Centers for Disease Control and Prevention, Atlanta, Georgia, USA (C.Y. Atkins, A. Patel, T.H. Taylor, Jr., M. Biggerstaff, T.L. Merlin, S.M. Dulin, B.A. Erikson, R.H. Borse, M.I. Meltzer); IMS Health, Fountain Hills, Arizona, USA (R. Hunkler)

Main Article

Table 4

Estimated number of influenza antiviral drugs prescribed for treatment, after adjusting for prescriptions for prophylaxis, nonadherence, and personal stockpiling, pandemic (H1N1) 2009 outbreak, United States

Influenza antiviral drug* No. prescriptions, by patient age group†
0–17 y 18–64 y >65 y
Oseltamivir 2,152,915 2,979,711 297,700 5,430,326
Subtotal‡ 2,209,980 3,058,690 305,591 5,574,262

*These antiviral drugs were prescribed in a variety of forms (e.g., capsules, tablets, syrup, and inhaled powder). The estimated numbers came from the IMS database (3), which records ≈73% of all prescriptions filled by >50,000 US-based retail pharmacies. IMS then proportionately extrapolates their data, based on populations served by pharmacies, to provide weekly estimates of all prescriptions filled in the U.S. for these drugs. The IMS Health Xponent database does not cover in-hospital prescriptions.
†These subtotals, by age group, are the estimates of prescriptions filled to treat pandemic (H1N1) 2009–related clinical illness, after removing the prescriptions filled for prophylaxis and for patients who failed to adhere to drug regimen or prescriptions filled for personal stockpiles (see Table 1). The total number of prescriptions filled, before adjustments, was 8,177,542 (Table 1). Note that ≈3% of prescriptions filled during this period did not have age of patient recorded, and we omitted those prescriptions from our calculations.
‡These subtotals, by age group, were the estimates used to calculate the hospitalizations averted as shown in Table 5.

Main Article