Table 2.

Effect of Various Antibiotics on Stable INRs in Acutely Ill Outpatients

	N	Median f/u (d)	Mean INR change	INR increase ≥therapeutic (%)	INR increase ≥1 (%)	INR increase ≥2 (%)	Absolute INR≥4 (%)	Absolute INR≥5 (%)
Terazosin	20	17.5	−0.145	5	0	0	0	0
Azithromycin	32	7	0.51*	31*	19	9	16	3
Levofloxacin	27	6	0.85†	33*	30†	11	19	11
TMP/SMX	16	6	1.76‡	69‡	56‡	38†	44†	31*

^*P value<.05 versus terazosin

^†P value<.01 versus terazosin

^‡P value<.001 versus terazosin

TMP/SMX, trimethoprim/sulfamethoxazole; INR, international normalized ratio