2024 article

Pharmacokinetics of intranasal and intramuscular flunixin in healthy grower pigs

Wiloch, E. E., Enomoto, H., Smith, L., Baynes, R. E., & Messenger, K. M. (2024, January 11). JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS.

author keywords: analgesia; flunixin; intranasal; pharmacokinetics; swine
TL;DR: Intranasal flunixin has similar, although variable, pharmacokinetic parameters to the intramuscular route, making it a viable route of administration for use in grower swine, according to this study. (via Semantic Scholar)
Source: Web Of Science
Added: January 16, 2024

AbstractFlunixin meglumine is a nonsteroidal anti‐inflammatory drug approved to manage pyrexia associated with swine respiratory disease. In the United States, no analgesic drugs are approved for use in swine by the FDA, although they are needed to manage painful conditions. This study evaluated the pharmacokinetics and relative bioavailability of intranasal versus intramuscular flunixin in grower pigs. Six pigs received 2.2 mg/kg flunixin either intranasally via atomizer or intramuscularly before receiving flunixin via the opposite route following a 5‐day washout period. Plasma samples were collected over 60 h and analysed using ultra‐performance liquid chromatography and tandem mass spectrometry to detect flunixin plasma concentrations. A non‐compartmental pharmacokinetic analysis was performed. The median Cmax was 4.0 μg/mL and 2.7 μg/mL for intramuscular and intranasal administration, respectively, while the median AUCinf was 6.9 h μg/mL for intramuscular administration and 4.9 h μg/mL for intranasal administration. For both routes, the median Tmax was 0.2 h, and flunixin was detectable in some samples up to 60 h post‐administration. Intranasal delivery had a relative bioavailability of 88.5%. These results suggest that intranasal flunixin has similar, although variable, pharmacokinetic parameters to the intramuscular route, making it a viable route of administration for use in grower swine.