Pharmacokinetic Study of Hydrocodone/APAP in Chronic Pain Patients

Hydrocodone combinations are the most commonly prescribed pain medications in the United States. All the current available Hydrocodone formulations are short acting and have Acetaminophen/Ibuprofen in them. Chronic pain patients who take pain medications for extended time are overloaded with Acetaminophen and there is a very serious concern about liver failure from excessive concurrent alcohol use. Also all the current hydrocodone combinations available in the U.S. are short acting and provide pain relief for 3-6 hrs. Hydromorphone is a metabolite of Hydrocodone and plays a significant role in providing pain relief in these patients. Although there are no long acting or extended release hydrocodone formulations that are FDA approve at this time, there is once a day extended release Hydromorphone (ER) approved by FDA and is currently marketed under the name Exalgo ®. PK study of chronic hydrocodone/acetaminophen usage is important to determine equivalent potency with hydromorphone ER, so that clinicians can use a simple conversion formula to switch to hydromorphone ER. Although medical professionals use the Opiate conversion formula on a regular basis for Opioid rotation, there are no published studies showing the pharmacokinetic data in patients taking hydrocodone for chronic pain. Our goal is to use this PK data to guide clinicians with this data in using extended release hydromorphone for chronic pain management to provide predictable pain relief and minimize the acetaminophen usage.