Is Thiamine (B1) Safe with Torsemide?
Free · No account · based on published sources including NIH ODS, FDA drug labels, and peer-reviewed literature
Patients with heart failure taking torsemide long-term should discuss prophylactic thiamine supplementation with their cardiologist or pharmacist.
Why this interaction occurs
Loop diuretics including torsemide increase urinary thiamine excretion. In heart failure patients, thiamine deficiency can create a paradoxical worsening of cardiac output (wet beriberi/high-output state), undermining the therapeutic goals of diuretic therapy. Clinical studies have demonstrated improved cardiac function in heart failure patients after thiamine supplementation.
Evidence
Evidence level: moderate.
Reported safety data
The FDA’s adverse event reporting system (FAERS) has received 33,353 reports mentioning Torsemide. This reflects reported cases involving the medication in general — not confirmed causation, and not specific to the Torsemide + supplement combination on this page.
FAERS reports are voluntary and cannot prove that a drug caused an event. Do not use report counts to assess the safety of this specific drug-supplement pair.
Frequently asked questions
Related interactions
All Thiamine (B1) interactions → · All Torsemide interactions →
Already checked this one — check your whole list
Educational only — not medical advice.
Always confirm with your doctor or pharmacist.