Opioid Potency: Oxycodone vs. Hydrocodone
Oxycodone is more potent than hydrocodone, with oxycodone being approximately 1.5 times more potent than hydrocodone when administered orally. 1
Comparative Potency and Pharmacology
Oxycodone is approximately 1.5 times more potent than hydrocodone when administered orally, meaning that 5mg of oxycodone provides roughly equivalent analgesia to 7.5mg of hydrocodone 1
Both medications are semi-synthetic opioid agonists that act primarily on μ-opioid receptors to provide analgesia 2
The relative potency difference is reflected in common combination formulations:
Clinical Implications of Potency Differences
Efficacy and Pain Relief
- Despite the potency difference, both medications provide similar efficacy when dosed appropriately 1
- When comparing equianalgesic doses, there is no substantial difference in pain relief between properly dosed hydrocodone and oxycodone 3
Metabolism and Predictability
- Both hydrocodone and oxycodone have more predictable metabolism compared to codeine 1
- Unlike codeine, neither medication is significantly affected by CYP2D6 polymorphisms that can cause unpredictable responses in 7-10% of Caucasians and up to 30% of Asians 1
Side Effect Profiles
- At equianalgesic doses, hydrocodone and oxycodone have similar side effect profiles including:
- Respiratory depression
- Constipation
- Nausea/vomiting
- Sedation 1
Patient Selection Considerations
When to Consider Oxycodone
- For patients requiring more potent analgesia in a smaller pill form 1
- When hydrocodone has provided inadequate pain relief at appropriate doses 2
- In patients who have demonstrated tolerance to hydrocodone 4
When to Consider Hydrocodone
- For opioid-naïve patients with moderate pain 1
- For patients who are more risk-averse (studies show hydrocodone is often preferred by risk-averse patients, particularly women and elderly individuals) 4
- When a slightly lower abuse potential is desired (though the difference is modest) 5
Important Caveats
Despite theoretical differences in potency, research has shown that the abuse liability profiles of hydrocodone and oxycodone do not differ substantially when equianalgesic doses are compared 5
Patient perception of "high quality" euphoria is stronger with oxycodone, which may contribute to its higher abuse potential despite similar pharmacological profiles 4
When prescribing either medication, limiting the duration of use is critical, as longer opioid use duration is associated with increased risk of depression, regardless of the specific opioid prescribed 6
Recent research indicates that intravenous oxymorphone (a metabolite of oxycodone) is significantly more potent than other opioids, being 12.5-14 times more potent than oxycodone and 2.3-2.8 times more potent than hydromorphone for abuse-related outcomes 7
In clinical practice, the potency difference between oxycodone and hydrocodone should be considered when switching between these medications to ensure appropriate dosing and prevent under or overdosing of patients requiring opioid analgesia.