Lorazepam study points to fewer repeat blockages in male cats
Version 1
A prospective, randomized, double-blinded, placebo-controlled JAVMA study suggests lorazepam may lower the risk of repeat urethral obstruction in male cats after a first obstruction episode. The trial enrolled 80 client-owned male cats treated at a university teaching hospital between 2021 and 2025, excluding cats with urolithiasis or urinary tract infection, and was published online in early May 2026. Independent summaries of the paper report that recurrence dropped from 15.7% in the placebo group to 0% in the lorazepam group, with no meaningful safety signal identified in the study summary available online. The broader clinical context also matters: feline urethral obstruction is a true emergency that can lead to severe hyperkalemia, acidosis, arrhythmias, bladder rupture, uroabdomen, acute kidney injury, and death without prompt treatment. (vetree.app)
Why it matters: Re-obstruction remains one of the most frustrating parts of managing feline urethral obstruction, with prior literature commonly citing recurrence rates in the roughly 15% to 40% range and noting that evidence for commonly used antispasmodics has been mixed. The rationale for lorazepam is biologically plausible in the first-time, non-stone, non-UTI cats studied here, because many obstructions are thought to reflect a mix of plugs, inflammation, edema, stress, and functional urethral spasm rather than a fixed mechanical lesion. If the full paper holds up under close reading, lorazepam could give veterinarians a new, evidence-based option for reducing early recurrence in carefully selected first-time blocked male cats, especially where stress, urethral spasm, and post-catheter irritation are thought to contribute. (pubmed.ncbi.nlm.nih.gov)
What to watch: Watch for clinician uptake, conference discussion, and whether follow-up studies confirm the benefit, define dosing and duration more clearly, and show whether results generalize beyond first-time, non-urolith, non-UTI cases. It will also be worth watching whether the paper changes how clinicians think about recurrence prevention more broadly—not just catheterization and decompression, but also stress biology, smooth muscle relaxation, and discharge management in cats at risk of blocking again. (consultant.vet.cornell.edu)