Midodrine reduces incidence of fainting in younger patients

Researchers report in a newly published study of vasovagal syncope in younger, otherwise healthy patients, that treatment with oral midodrine significantly decreases fainting spells.

Vasovagal syncope is the most common cause of fainting, and it happens when the blood vessels open too wide and/or the heartbeat slows.

The findings were published on August 3, 2021 in Annals of Internal Medicine.

“Recurrent vasovagal syncope is common, responds poorly to treatment, and causes physical trauma and poor quality of life,” the authors said. They noted that prior research had shown that, “Midodrine prevents hypotension and syncope during tilt tests in patients with vasovagal syncope.”

The purpose of the new study was to evaluate whether midodrine also prevents vasovagal syncope in usual clinical conditions. The study included patients with recurrent vasovagal syncope and no serious comorbid conditions.

The investigators enrolled 133 subjects, The average age was 32 years, 73% were female, they had started fainting at an average age of 17 and they had fainted an average of 6 times during the year before enrolling in the study.

The researchers randomized the subjects 1:1 to placebo or to 3-times-daily midodrine. They followed the subjects for 12 months.

The primary endpoint was the proportion of subjects with at least 1 syncope episode during the 12-month follow-up.

All subjects received education on the pathophysiology of vasovagal syncope and conservative prevention measures including physical maneuvers and dietary advice.

Compared with those who received placebo, fewer midodrine-treated subjects had at least 1 syncope episode — 28 of 66 (42%) vs. 41 of 67 (61%), a 19% absolute risk reduction. (P = 0.035).

The authors concluded, “Midodrine can reduce the recurrence of syncope in healthy, younger patients with a high syncope burden.”