Table 1.

Outpatient Antibiotic Prescription Fills in the United States, August 2014 Through July 2020

	Estimated Monthly Prescription Fills,a Base Levelb		Monthly Trend in Prescription Fills,a August 2014–March 2020			Change in Prescription Fills,a April 2020c				Monthly Trend in Prescriptions Fills,a April 2020–July 2020			Relative Change in Trend of Monthly Prescription Fills,a April 2020—July 2020d
Antibiotic	No. of Prescriptions	95% CI	Monthly Trend	95% CI	P Value	Change, %	Change, No.a	95% CI	P Value	Monthly Trend	95% CI	P Value	Monthly Trend	95% CI	P Value
Amoxicillin	16.12	14.46 to 17.77	–0.007	–0.040 to 0.259	.68	–56	–8.69	–10.02 to –7.37	<.001	1.248	1.033 to 1.463	<.001	1.255	1.034 to 1.476	<.001
Azithromycin	14.07	11.66 to 16.47	–0.438	–0.092 to 0.004	.07	–49	–5.01	–7.26 to –2.77	<.001	–0.121	–0.884 to 0.642	.75	–0.077	–0.845 to 0.690	.84
Amoxicillin-clavulanate	7.35	6.36 to 8.33	0.018	–0.003 to 0.038	.09	–49	–3.97	–4.90 to –3.05	<.001	0.182	–0.044 to 0.408	.11	0.164	–0.065 to 0.393	.16
Ciprofloxacin	6.72	6.46 to 6.98	–0.049	–0.053 to –0.045	<.001	–16	–0.54	–0.70 to –0.38	<.001	0.229	0.184 to 0.273	<.001	0.278	0.233 to 0.323	<.001
Cephalexin	5.78	5.54 to 6.02	0.0001	–0.005 to 0.005	.94	–27	–1.70	–1.92 to –1.47	<.001	0.655	0.574 to 0.736	<.001	0.655	0.573 to 0.736	<.001
Sulfamethoxazole-trimethoprim	5.71	5.51 to 5.90	–0.192	–0.023 to –0.016	<.001	–20	–0.84	–1.00 to –0.69	<.001	0.258	0.214 to 0.302	<.001	0.277	0.232 to 0.322	<.001
Levofloxacin	4.09	3.64 to 4.51	–0.03	–0.037 to –0.022	<.001	–38	–0.64	–0.91 to –0.38	<.001	0.033	–0.03 to 0.097	.30	0.063	–0.001 to 0.127	.06
Doxycycline	3.87	3.66 to 4.08	0.036	0.030 to 0.042	<.001	–25	–1.62	–1.93 to –1.30	<.001	0.157	0.089 to 0.225	<.001	0.121	0.052 to 0.189	.001
Clindamycin	2.61	2.51 to 2.71	–0.003	–0.004 to –0.001	.005	–29	–0.67	–0.74 to –0.59	<.001	0.242	0.205 to 0.298	<.001	0.244	0.208 to 0.281	<.001
Nitrofurantoin	2.28	2.18 to 2.38	0.013	0.012 to 0.015	<.001	–13	–0.48	–0.59 to –0.36	<.001	0.183	0.145 to 0.222	<.001	0.17	0.131 to 0.209	<.001

Data were analyzed using a interrupted time-series regression model with Newey-West standard errors (STATA 16.1). Significant results appear as bolded text.

^aPresented as prescription fills per 1000 persons, using US Census monthly estimates of the national population.

^bEstimated number of prescription fills per 1000 persons at start of prepandemic period.

^cChange in prescription fills from March 2020 to April 2020, based on values from predicted trends for each drug (Supplementary Figure 1).

^dChange in trend for April 2020 through July 2020, relative to August 2014 to March 2020.