Numerous articles have described the methodologies used and outcomes achieved with the intrathecal (IT) administration of morphine for pain. However, only one case report has been published that describes converting a patient’s IT morphine to an oral regimen. This case report describes the experience of converting a patient’s IT morphine to oral morphine and discusses the scarcity of published data to validate suggested equianalgesic intraspinal morphine recommendations. The calculated equianalgesic oral to IT ratio in this case was 12:1. This is substantially lower than the 300:1 ratio published by Krames and the 90:1 ratio employed by a commercially available software program for calculating equianalgesic opioid doses. We recommend caution when applying existing guidelines for conversion of morphine from an IT to an oral regimen.
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