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In foals, romifidine was reported to produce sedation and analgesia with greater intensity and longer duration than xylazine [99]. Celly et al. [82] reported that romifidine at 0.05 mg/kg IV produced a similar degree of hypoxemia but a significantly longer duration of initial hypertension than other α₂ agonists. When xylazine (0.15 mg/kg IV), detomidine (0.03 mg/kg IV), romifidine (0.05 mg/kg IV), and medetomidine (0.01 mg/kg IV) were administered to sheep at quasiequipotent doses, similar decreases in PaO₂ and increases in respiratory rate and maximum changes in transpulmonary pressure (ΔP _pl) were observed with all four drugs except the duration of increase in respiratory rate, and ΔP _pl were longest with romifidine [82].

When romifidine (0.05 mg/kg) was administered by lumbosacral epidural injection, it produced moderate to complete analgesia of the perineum, flank, and abdominal regions. Increasing the dose to 0.075 mg/kg did not enhance the degree of analgesia but only prolonged the duration. Khattri et al. [100] indicated that higher doses of romifidine (0.075 mg/kg) produced a wider region of analgesia from the tail regions to the thorax. This may be the result of a higher concentration of the injected drug solution with 0.075 mg/kg than 0.05 mg/kg since the total volume of the injected solution was maintained at the same 4 ml for both dosages in this study. Side effects resulting from spinally administered romifidine included dose‐dependent ataxia and decreased heart rate, respiratory rate, and mean arterial blood pressures [100].

In camels, the sedative and analgesic effects of romifidine were assessed at three different doses (0.04, 0.08, and 0.12 mg/kg IV). Both the sedative and analgesic effects were dose dependent with the duration of sedation (37, 51, and 65 minutes, respectively) lasting longer than the analgesic effect (21, 34, and 46 minutes, respectively). Bradycardia, ruminal tympany, increased urine output, and hyperglycemia are commonly observed side effects during romifidine sedation. Camels may not represent domestic camelids like llamas and alpacas, and they have been reported to require higher doses of xylazine to produce a similar degree of sedation. Thus, llamas and alpacas may require a lower dose of romifidine to produce desirable sedation and analgesia [101].