Torsemide

What is this medication for?

• Adjunctive CHF therapy when refractory to furosemide (or as furosemide alternative)

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• Hyponatremia (greatest concern), hypokalemia, hypocalcemia, hypomagnesemia (Fluid/electrolyte depletion, esp. anorexic patients)
• stomach/intestinal disturbance, low red blood cell counts/low white blood cell counts, weakness, restlessness (Possible)

Worth a phone call to your veterinarian

• Prerenal rising kidney values (With moderate–severe dehydration)
• Ototoxicity (Rare (unlike furosemide); only at very high lab-animal doses)

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Trouble breathing, collapse, seizures, severe vomiting or diarrhea, facial swelling, or pale gums

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: Hypersensitivity (sulfonylureas); anuria
• has or has had: Significant hepatic dysfunction; hyperuricemia; diabetes mellitus (may ↑ glucose); dehydration

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • ACE inhibitors
  • Other diuretics/electrolyte-depleting drugs
  • Ototoxic drugs (aminoglycosides)

Storage and handling

Room temperature. Oral tablets only in the USA. into a vein (where available) over ≥2 minutes (ototoxicity with rapid into a vein in humans).

Good to know

• Conversion rule of thumb: torsemide ≈ 10× furosemide potency — start at one-tenth of the furosemide dose (e.g., furosemide 2 mg/kg every 12 hours → torsemide 0.2 mg/kg every 12 hours).
• Diuretic resistance developed after 14 days on furosemide but NOT with torsemide in the Hori 2007 comparison — the main rationale for switching refractory patients.
• More potassium-sparing than furosemide in DOGS (Na:K excretion ratio ~2× furosemide's); in cats potassium effects are similar to furosemide.
• Both drugs raised BUN/creatinite in that study — renal monitoring is still mandatory.