Table 1.

Characteristics of included studies

Study	Study design	Interventions		Sample size		Age in years (mean ± SD)	Previous syncopal episodes	Outcome	Follow-up duration
		Midodrine	Control	Midodrine	Control
Kaufmann 2002	Double-blind crossover RCT	5 mg PO single dose	Matching placebo	12	12	42 ± 4	Range 2 to > 15	HUT-induced syncope	3 days
Ward 1998	Double-blind crossover RCT	5 mg tid PO	Matching placebo	16	16	56 ± 18	Range 2 to 8	HUT-induced syncope	2 months
Liu 2009	Open label RCT	1.25–2.5 mg bid PO	Conventional therapy	15	33	11 ± 3	Not reported	HUT-induced and clinical syncope	9 months
Qingyou 2006	Open label RCT	1.25–2.5 mg bid PO	Conventional therapy	12	10	12 ± 3	Range 3 to 40	HUT-induced syncope or severe presyncopea	10 months
Perez-Lugones 2001	Open label RCT	5–15 mg tid PO	Conventional therapy	31	30	42 ± 17	Range 9 to 41	Clinical Syncope	12 months
Romme 2011	Double-blind crossover RCT	5 mg bid PO	Matching placebo	23	23	31 ± 12	IQR 20 to 90	Clinical syncope	6 months
Sheldon 2021	Double-blind RCT	2.5–10 mg tid PO	Matching placebo	66	67	36 ± 13	Midodrine IQR 10 to 100 Placebo IQR 11 to 250	Clinical syncope	12 months

HUT, head-up-tilt; IQR, interquartile range; RCT, randomized controlled trial.

^aSymptoms of severe pre-syncope accompanied by hypotension or bradycardia.