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More recently, α₂‐adrenergic agonists and opioids either alone or in combination with local anesthetic solutions have been used for epidural anesthesia. Epidural administration of the α₂‐agonist xylazine hydrochloride (0.05 mg/kg) diluted in 5–12 ml of sterile saline or xylazine hydrochloride (0.3 mg/kg) added to 5 ml of 2% lidocaine hydrochloride offer similar anesthesia to lidocaine. Although the duration of anesthesia is prolonged (four to five hours) using these combinations, systemic effects (sedation, salivation, ataxia) may also occur [1]. Epidural administration of opioids, such as morphine (0.1 mg/kg) diluted in 20 ml of sterile saline, is used to provide analgesia for a prolonged period (approximately 12 hours) without interfering with motor function. Disadvantages of using opioids for epidural anesthesia are that the analgesia is not as potent as lidocaine and the maximum effect of a morphine epidural may not occur for two to three hours. Caudal epidural administration of morphine may be used to help alleviate pain in the perineal area and straining [8].

Alcohol has been used previously to desensitize the perineum for a prolonged period and in some cases permanently. Alcohol administered by this route can lead to demyelination of nerves. This can result in damage more cranial than the perineum and could effectively paralyze the patient if it were to travel up the nerve root and into the sciatic nerve. Therefore its use in epidural anesthesia is not recommended [9].