After castration in horses: longer vs single-dose flunixin course — MAYBE (weak evidence)

STAMP: MAYBE (weak evidence): No eligible record exists for this shelf, and this pack is honestly empty (no cards). PubMed searches run at drafting (Nov 10, 2026 — flunixin combined with castration, pain, swelling/oedema and healing in horses, including 'single dose versus repeated', 'course length' and 'days of treatment' phrasings) found NO study that compares a longer course of flunixin meglumine with a single dose of flunixin meglumine in horses after castration, on pain, swelling, or healing — so there is no direct evidence on whether extra days of flunixin reduce pain and swelling, and none at all on whether they delay healing. Near-misses, documented here and deliberately not carded: (1) Gobbi 2020 (PMID: 33077071) randomised the drug, not the duration: 30 horses after open castration received flunixin meglumine (1.1 mg/kg IV once daily for 5 days), firocoxib (0.1 mg/kg IV once daily for 5 days) or meloxicam (0.6 mg/kg IV once daily for 5 days), 10 per group — every arm was a 5-day course, and there was no single-dose arm; limb rigidity and prepuce oedema scores were greater in the firocoxib and meloxicam groups than in the flunixin group, and the authors conclude all three drugs were equally effective in controlling pain and inflammation after castration, with flunixin more advantageous. This shows a 5-day flunixin course is a studied regimen, not that it beats one dose. (2) Sanz 2009 (PMID: 19912042), a randomised controlled trial in 36 colts undergoing routine castration, compared butorphanol alone, phenylbutazone alone (4.4 mg/kg IV before surgery, then 2.2 mg/kg PO q12h for 3 days) and the combination, with placebos used to balance protocols: at no time point did assessed variables or signs of pain differ significantly among groups — a multi-day course of a different NSAID, with no flunixin arm and no duration contrast. (3) Prügner 1991 (PMID: 1920607): in the castration study, two groups of 10 colts received eltenac (1 mg/kg) or placebo injections on three consecutive days after surgery, and eltenac significantly inhibited pain and swelling, the effect maintained for up to 48 hours after the last injection — evidence that a 3-day NSAID course can beat placebo on post-castration swelling, but for eltenac, not flunixin, and against placebo rather than against a single dose. (4) Love 2009 (PMID: 19803050), a randomised observer-blinded study in 20 ponies, found a single preoperative dose of butorphanol did not provide adequate postoperative analgesia after castration (pain scores not significantly different between groups, P = 0.063; flunixin appears only as second-line rescue analgesia) — a single-dose inadequacy signal for an opioid, not a flunixin course comparison. (5) Alipour-Khairkhah 2025 (PMID: 39835330) gave flunixin or no flunixin to 20 male donkeys undergoing surgical or bloodless castration and found flunixin reduced inflammatory and stress markers — donkeys are not this shelf's population (horses), and the contrast is drug vs no drug, not course length. No fetched record measured wound healing as an outcome of flunixin duration after castration, so the 'without delaying healing' half of the question is entirely untested in the records found. Design class (c): randomisation is not established, because no eligible record exists at all. One-home cross-point: flunixin vs firocoxib for post-operative COLIC pain homes on shelf #200 — a different procedure (intestinal surgery, not castration) — and none of its records are re-carded here. Tier C is not engaged (no mortality/survival claim). Drafted Nov 10, 2026 (VetMed build, topic #813); all figures from the abstracts fetched and verified at drafting.