Abstract：Objective To explore the correlation between doxycycline steady-state blood drug concentration and coagulation function indicators in patients with severe pulmonary infections,providing a basis for clinical individualized medication. Method A total of 110 patients with severe pulmonary infections admitted to our ICU from January 2023 to January 2025 were prospectively included and divided into an observation group(n=60)and a control group(n=50)based on whether doxycycline was used or not.On the third day of administration,the observation group measured the steady-state peak concentration(C0)and trough concentration(C0),and dynamically monitored the prothrombin time(PT),activated partial thromboplastin time(APTT),thrombin time(TT),fibrinogen(FIB),international normalized ratio(INR),and platelet count(PLT)of both groups before treatment and on the third and seventh days of treatment.Pearson correlation and multiple linear regression were used to analyze the relationship between blood drug concentration and coagulation indicators. Result On the third day of treatment,PT,APTT,and INR in the observation group significantly increased compared to baseline(P<0.05),while FIB and PLT significantly decreased(P<0.05).On the seventh day,they returned to baseline levels;There was no significant difference in the indicators of the control group before and after treatment(P>0.05).The observation group's doxycycline C2 was(3.28±1.15)μg/mL,and C0 was(1.46±0.62)μg/mL.C2is significantly positively correlated withΔPT,ΔAPTT,and ΔINR(r=0.582,0.517,0.603,P<0.001),and significantly negatively correlated with ΔFIB and ΔPLT(r=-0.493,-0.446,P<0.01);There is no significant correlation between C0 and various indicators.Multiple regression analysis showed that doxycycline C0(β=0.412),combined use of cefoperazone sulbactam(β=0.306),and baseline APTT prolongation(β=0.251)were independent risk factors for PT elevation(P<0.05). Conclusion Doxycycline can cause transient coagulation dysfunction in patients with severe pulmonary infections,with the degree of impact significantly correlated with the steady-state peak concentration.When C0>3.95 μg/mL,the risk of coagulation dysfunction increases significantly.It is recommended to monitor blood drug concentrations clinically and avoid concomitant use with cefoperazone-sulbactam.
张沛, 李楠, 韩佳琳. 重症肺部感染患者多西环素血药浓度与凝血功能指标的相关性研究[J]. 哈尔滨医药, 2026, 46(2): 7-10.
Zhang Pei, Li Nan, Han Jialin. Study on the Correlation between Doxycycline Blood Concentration and Coagulation Function Indicators in Patients with Severe Pulmonary Infection. journal1, 2026, 46(2): 7-10.
2026, Vol. 46 
