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The most commonly recommended volume of epidurally administered drugs in the literature, irrespective of the drug, is 10–15 mL per horse (for an average size horse weighing 500 kg), to avoid excessive cranial migration and hind limb ataxia. However, higher volumes (20–30 mLs) of diluted drugs that do not cause motor deficits (i.e. opioids) have been administered without causing ataxia.

In pregnant mares or obese horses, the total volume of epidural solutions should be reduced as the cranial spread is increased.

When a local anesthetic and an alpha‐2 adrenergic agonist are combined, the dose of the local anesthetic should be reduced. Less lipophilic alpha‐2 adrenergic agonist drugs with less systemic absorption are preferred by the author (e.g. xylazine instead of detomidine) as they cause less systemic effects and have a longer duration of spinally‐mediated analgesia.

Slow injection (<1 mL/10 seconds) of epidural solutions while the horse is observed for signs of discomfort and ataxia is recommended and the injection should be slowed or halted if these signs appear.