Buprenorphine is commonly used as (part of) postoperative
analgesic treatment with dosage dependent side-effects such as
pica behaviour. No strict consensus exists about the optimal dosing interval of
buprenorphine, as its duration of action has been described as being in the range of 6-12 h. In this study, dosing intervals of 8 h (thrice-a-day) and 12 h (twice-a-day) for
buprenorphine in a multimodal
analgesic strategy (concurrent administration of a non-steroidal anti-inflammatory
drug) were compared on food intake, weight and side-effects (gnawing on
plastic Petri dishes and growth rate, indicative of
pica behaviour) in rats. The food intake and weight of both intervals were comparable, as the animals from the twice-a-day group did not lose more weight or consumed less food during the
analgesic period. The rats from the thrice-a-day group suffered from more side-effects, as the growth rate was decreased and more
plastic was gnawed on. It is recommended to carefully evaluate
analgesic and side-effects when using
buprenorphine. When side-effects are observed, the possibility of increasing the dosing interval of
buprenorphine should be explored. In this study, increasing the dosing interval of
buprenorphine in a multimodal
analgesic regimen resulted in reduced unwanted side-effects, without increasing
weight loss or decreasing food intake. Although this is suggestive of provision of comparable
analgesia, future studies including more
pain-related readout parameters to assess the effect of the dosing interval on
analgesic efficacy are recommended.