The peri / postoperative analgesic effect of intravenous paracetamol in dogs



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PICO Question

In healthy dogs undergoing a surgical procedure, is there improved pain control in dogs receiving intravenous paracetamol in the peri / postoperative period compared to dogs not receiving intravenous paracetamol?


Clinical bottom line

Category of research


Number and type of study designs reviewed

Three randomised, controlled, and blinded studies. Two studies directly address the PICO question whereby postoperative pain assessment was clinically evaluated following intravenous (IV) paracetamol. The third study addressed the question to a lesser extent, whereby the impact on the sevoflurane minimum alveolar concentration (MAC) reduction in response to noxious stimuli was assessed following the administration of IV paracetamol.

Strength of evidence


Outcomes reported

The findings of the first two studies presented appear to directly contradict each other. The first study demonstrated a reduction in pain in all groups and found no differences in analgesia between IV paracetamol and other non-steroidal anti-inflammatories drugs (NSAIDs), while the second study reported no analgesia effects from IV paracetamol and was terminated prematurely because a high number of dogs required rescue analgesia. The first study reported sufficient analgesic effects of IV paracetamol and the second study reported no analgesia effects of IV paracetamol. Both were blinded, randomised, controlled studies and directly addressed the PICO question in relation to the peri / postoperative analgesic effects of IV paracetamol. However, their methods and sample sizes were very different. The third study did not demonstrate a clinically relevant sevoflurane MAC reduction after IV paracetamol in dogs.


At present, there is limited and weak evidence to suggest that IV paracetamol provides peri / postoperative analgesia in dogs. However, further studies are required to better assess its efficacy, its duration of action, and the appropriate doses that are necessary to reach therapeutic plasma levels. The reduced incidence of side effects at the currently recommended doses could support its peri / postoperative use, where NSAIDs use is contraindicated.


How to apply this evidence in practice

The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources.

Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.


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Vol. 9 No. 2 (2024): The second issue of 2024

Section: Knowledge Summaries

Categories :  Small Animal  /  Dogs  /  Cats  /  Rabbits  /  Production Animal  /  Cattle  /  Sheep  /  Pig  /  Equine  /  Exotics  /