Table 1.

Basic features of the included study.

Studies	Sample (n)		Gender (male/female)	Age (Year)	Average course of disease (week)	Outcomes	Course (week)	Adverse reactions	Interventions
	E	C							Experimental group	Control group
Bai 2010 [27]	19	20	23/16	68 ∼ 76	E : > 3; C : > 3	Clinical efficiency	52	Not described	Ligustrazine injection, prednisone, routine treatment	Prednisone, routine treatment
Huang 2010 [28]	30	30	E : 15/15; C : 14/16	E : 50∼70; C : 52∼71	E : 5∼ 54; C : 5∼ 60	Clinical efficiency, TLC %, DLCO %, VC %	12	Not described	Ligustrazine injection	Prednisone
Liu 2015 [29]	35	35	E : 29/6	E : 55.8 ± 12.9	——	Clinical efficiency, TLC %, DLCO %, VC %, PaO2	12	E : 7/35 (edema in 2 cases, hypertension in 2 cases, gastrointestinal bleeding in 2 cases and depression in 1 case)	Ligustrazine injection, budesonide, routine treatment	Budesonide, routine treatment
			C : 28/7	C : 53.6 ± 11.7	——			C : 7/35 (edema in 3 cases, hypertension in 1 case, hyperglycemia in 1 case, oral infection in 1 case, and bone pain in 1 case)
Wang 2007 [30]	56	30	E : 36/20	26–58	2–12	Clinical efficiency	Unclear	Not described	Ligustrazine injection	Prednisone
			C : 18/12
Wang 2013 [31]	16	16	16/16	42 ∼ 70	36–96	Clinical efficiency, PaO2	2	Not described	Ligustrazine injection, prednisone, routine treatment	Prednisone, routine treatment
Yang 2004 [32]	15	15	E : 11/4	E : 53.15 ± 12.2	——	Clinical efficiency	8	E : 0/15	Ligustrazine injection, routine treatment	Prednisone, routine treatment
			C : 10/5	C  55. 09 ± 12.4	——			C : 5/15 (gastric discomfort)
Yu 2016 [33]	25	24	27/22	55–82	3–18	Clinical efficiency, TLC %, DLCO %, VC %, PaO2	4	Not described	Ligustrazine injection, methylprednisolone, routine treatment	Methylprednisolone, routine treatment

Note: E: experimental group; C: control group.