Efficacy of transdermal ketoprofen on surgical inflammation in dogs

Ketoprofen is a non-steroidal anti-inflammatory drug (NSAID) used to treat pain and inflammation in dogs. Despite having effective analgesic efficacy, prolonged oral administration has been associated with adverse effects. Transdermal delivery of ketoprofen has reduced the incidence of adverse effects in humans and could potentially be used in veterinary clinical medicine. A transdermal (TD) ketoprofen formulation was recently developed for use in dogs and this study aimed to determine the pharmacodynamic activity of this formulation using surgical castration as an acute inflammatory model. Twelve dogs were randomly assigned to either a Control group (n = 6) or a TD group (n = 6). All dogs were castrated using standard surgical protocols, administered with pre-medication, consisting of acepromazine (0.055 mg/kg) and methadone (0.5 mg/kg) intramuscularly (IM) 30 min prior to induction of general anaesthesia. All dogs were then anaesthetised by injecting alfaxalone (2 mg/kg IV) via a 20 G 3 cm catheter in the left cephalic vein and subsequently maintained using isoflurane. Along with that TD group dogs also received TD ketoprofen (10 mg/kg) 1 h before pre-medication. Bloods were collected at 0 - hour (pre-surgery), and 1 and 2-h post-surgery and analysed for circulating eicosanoids using liquid chromatography mass spectrometry (LCMS) methods. Measured levels of Thromboxane B₂ (TXB₂) at both 1 and 2 h and Prostaglandin E₂ (PGE₂) at 2 h post-surgery were higher in the Control group compared to the TD group, suggesting pre-operative application of TD ketoprofen has a possible inhibitory effect on systemic inflammation and could be used to treat pain and inflammation in dogs.