Pregabalin linked to slower MRI anaesthetic recovery in horses: full analysis
A new equine anaesthesia study suggests oral pregabalin may slow recovery after isoflurane anaesthesia in horses undergoing elective MRI, even if it doesn’t appear to worsen the quality of that recovery. In the retrospective cohort, published in Equine Veterinary Journal, horses that received pregabalin before anaesthesia took longer to stand than matched controls, with a median recovery time of 60 minutes versus 53 minutes. Recovery quality scores, however, were not significantly different between groups. (pmc.ncbi.nlm.nih.gov)
That distinction matters because recovery remains the most dangerous part of general anaesthesia in horses. Reviews of the literature and more recent retrospective analyses continue to describe the recovery phase as the period of greatest risk, with complications such as fractures, myopathy, and neuropathy carrying outsized consequences even in elective cases. MRI cases are especially relevant because they often involve otherwise stable horses anesthetized for diagnostic imaging rather than surgery, making medication effects on recovery easier to scrutinize. (pmc.ncbi.nlm.nih.gov)
In the new study, investigators evaluated 128 horses undergoing elective MRI of the appendicular skeleton, including 52 treated with pregabalin and 76 controls. Based on the study summary and available full-text details, pregabalin administration was associated with a statistically significant increase in time to standing, while overall recovery scores were unchanged. The authors’ model also linked longer recovery to increasing age, acepromazine administration, xylazine use during recovery, delayed first movement, and delayed extubation. In practical terms, the study points to pregabalin as one contributor within a broader recovery profile rather than a standalone explanation for every slow recovery. (pmc.ncbi.nlm.nih.gov)
There doesn’t appear to be a press release or broad industry response tied to the paper, but the result lands in a clinically active area. Recent equine MRI recovery research has focused on how commonly used behavior-modifying or analgesic drugs shape the post-anaesthetic period. One 2025 retrospective study from North Carolina State University reported that pre-anaesthetic trazodone did not significantly affect recovery scores, recovery duration, or sedative use in horses undergoing orthopedic MRI, underscoring that different pre-anaesthetic drugs may carry different recovery tradeoffs. (mdpi.com)
Why it matters: For veterinary professionals, this is a workflow and case-selection story as much as a pharmacology story. A seven-minute increase in median time to standing may sound modest, but in equine recovery, extra time on the ground can mean prolonged supervision, more recovery sedation decisions, delayed turnover of MRI and recovery facilities, and potentially more concern in horses already carrying risk factors for neuropathy or myopathy. The absence of a drop in recovery quality is reassuring, but it doesn’t fully neutralize the operational impact of a slower recovery in a species where the recovery window is already high stakes. (pmc.ncbi.nlm.nih.gov)
The study also raises a broader question about balancing pre-emptive analgesia against recovery efficiency. Pregabalin may still offer value in multimodal pain management, but this paper suggests teams should weigh that potential benefit against a measurable delay in standing recovery for MRI cases under isoflurane. Because the study was retrospective, it can show association, not causation, and unmeasured confounding is still possible. Even so, the findings are actionable enough to inform pre-anaesthetic discussions among anesthesiologists, internists, surgeons, and referring veterinarians. (pmc.ncbi.nlm.nih.gov)
What to watch: The next step is prospective, protocol-standardized work that can test pregabalin dose, timing, case selection, and interaction with other recovery drugs to determine whether the recovery delay is consistent, clinically meaningful across settings, and avoidable without giving up analgesic goals. (pmc.ncbi.nlm.nih.gov)