Table 2.

Exposure to Antibiotics and Other Medications Before Age 2 Years

No Antibiotics, N (%)	305,489 (44.8%)
Any Antibiotic, N (%)	376,250 (55.2%)
All Antibiotics, N (%)
1	144,949 (21.3%)
2	83,157 (12.2%)
3	50,870 (7.5%)
4+	97,267 (14.3%)
Narrow Spectrum, N (%)
1	159,295 (23.4%)
2	76,486 (11.2%)
3	34,326 (5.0%)
4+	23,512 (3.4%)
Broad Spectrum, N (%)
1	114,830 (16.8%)
2	47,440 (7.0%)
3	24,848 (3.6%)
4+	39,926 (5.9%)
Amoxicillin, N (%)
1	159,083 (23.3%)
2	76,096 (11.2%)
3	34,068 (5.0%)
4+	22,793 (3.3%)
Amoxicillin/Clavulanic Acid, N (%)
1	67,435 (9.9%)
2	19,121 (2.8%)
3	6,797 (1.0%)
4+	4,280 (0.6%)
Azithromycin, N (%)
1	46,191 (6.8%)
2	10,836 (1.6%)
3	3,719 (0.5%)
4+	2,371 (0.3%)