A single ingredient sustained release hydrocodone product to be called Zohydro is currently in phase 3 clinical trials by Zogenix, and if it gets FDA approval is likely to become the next Oxydontin as a drug of abuse and addiction potential. I watched a segment on the evening news this week about Zohydro, and it is certainly not going to come to market without fanfare. Experts on the newscast did a pretty fair job of outlining the concerns of Zohydro, the potential for abuse and the issues with high dose single ingredient opioid products. Opioid overdose is much more likely with drugs where a very high dose of the drug is contained in a single pill.
Oxycontin has a reputation as probably the most abused of the prescription opioids because of its lack of acetaminophen, its high percentage of rapid release oxycodone, and its lack of properties preventing crushing the pills which eliminates the extended release properties and makes it possible to inhale, inject or smoke the drug. Sometimes known as Hillbilly Heroin, Oxycontin is among the leading causes of prescription drug overdose deaths and opioid addiction in the U.S.
If Zohydro receives FDA approval as a single ingredient, high dose hydrocodone product there is little doubt that it will join Oxycontin as a major drug of abuse. Proponents of non-acetaminophen opioid pain medications are correct when they state that acetaminophen has its own problems, and especially when too many pain pills are taken to get pain relief the daily acetaminophen dosage can exceed the 4000 mg / day maximum safe dose. Serious and even fatal acetaminophen liver damage can result. Still single ingredient opioid products are so prone to diversion, addiction, and abuse that I anticipate that Zohydro, if approved, will quickly become a major drug of abuse.
One thing physicians have on our side now is the Oxycontin experience. We will be much more skeptical of allowing escalating Zohydro doseage and addiction become commonplace. Still I am not looking forward to one more drug with few advantages and much abuse potential coming to market.
Oxycontin is available in doses of 10, 15, 20,30, 40, 60 and 80 mg tablets. Using the recommended opioid Morphine Equivalent Dosage calculator available for download at the Agency Medical Directors site, 30 mg of morphine is equivalent to 30 mg of hydrocodone but to only 20 mg of oxycodone (i.e. oxycodone is 1.5 x as potent on a mg for mg basis than hydrocodone). Using these equivalency ratios it would be expected that Zohydro might become available in doses up to 120 mg per pill. This would make it highly popular as a drug of abuse, as current hydrocodone products all contain acetaminophen, and maximum hydrocodone dosing even with products with 10 mg hydrocodone and 325 mg acetaminophen are 12 tablets daily, making 120 mg of hydrocodone the maximum daily hydrocodone dosage.