Is hydrocodone (opioid medication) the same as oxycodone (opioid medication)?

Hydrocodone vs. Oxycodone: Are They the Same?

No, hydrocodone and oxycodone are not the same medication—they are two distinct opioid analgesics with different chemical structures, different DEA scheduling classifications, and importantly, different potency levels, with oxycodone being approximately 1.5 times more potent than hydrocodone. 1, 2

Key Differences Between the Medications

Chemical and Pharmacological Distinctions

• Hydrocodone is a mu- and delta-opioid receptor agonist that may be approximately equipotent with oral morphine, though its equivalence data are not fully substantiated 1
• Oxycodone is an opioid with agonist activity at the mu-, delta-, and kappa-opioid receptors, making it pharmacologically distinct from hydrocodone 1
• Potency difference: Oxycodone is generally 1.5 times more potent than hydrocodone, meaning 10 mg of hydrocodone is roughly equivalent to 6.7-7.5 mg of oxycodone 2

DEA Scheduling Classification

• Oxycodone is classified as Schedule II, whether alone (e.g., Roxicodone) or in combination products (e.g., Percocet, Percodan) 1
• Hydrocodone combination products (≤15 mg combined with acetaminophen or ibuprofen, such as Vicodin, Lortab) were historically Schedule III but have been reclassified to Schedule II due to increasing abuse potential 1

Clinical Efficacy Comparison

Pain Relief Equivalence

• When dosed at equianalgesic levels, both medications provide similar pain relief for acute pain 1
• Two prospective randomized controlled trials comparing short-acting oxycodone with hydrocodone combination products found them to be equal in pain relief when appropriately dosed 1
• In a 2005 study by Marco et al., oxycodone 5 mg/acetaminophen 325 mg showed no difference compared to hydrocodone 7.5 mg/ibuprofen 200 mg in pain relief, doses taken, or global efficacy evaluations over 8 days 1

Important Clinical Caveat

The key phrase here is "equianalgesic doses"—this means you cannot simply substitute one medication for another milligram-for-milligram. The dosing must account for the potency difference 1, 2.

Safety and Adverse Event Profiles

Risk of Long-Term Use

• Hydrocodone is associated with substantially higher rates of transition to long-term opioid use compared to oxycodone 3
• In primary care patients with acute back pain, an estimated 12% treated with hydrocodone transitioned to long-term use versus only 2% on oxycodone 3
• Among patients receiving more than one prescription, 23% on hydrocodone transitioned to long-term use versus 5% on oxycodone 3

Risk of Overdose

• Oxycodone carries a significantly higher risk of opioid overdose compared to hydrocodone 4
• After adjustment for patient characteristics, oxycodone showed an adjusted hazard ratio of 1.65 (95% CI 1.45-1.87) for overdose compared to hydrocodone 4
• Oxycodone monotherapy (without acetaminophen) greatly increases overdose hazard (aHR 2.18,95% CI 1.86-2.57) compared with hydrocodone/acetaminophen combinations 4
• Oxycodone combined with acetaminophen also shows increased overdose risk (aHR 1.26,95% CI 1.06-1.50), though not to the same extent as monotherapy 4

Abuse Potential Differences

• Oxycodone is preferred by substance abusers (44.7% vs 29.4% for hydrocodone) because 54% rated the quality of the high as much better 5
• Hydrocodone users tend to be more risk-averse (women, elderly, non-injectors) who prefer safer acquisition methods 5
• Oxycodone attracts risk-tolerant young males who prefer to inject or snort their drugs and use more aggressive diversion methods 5

Practical Conversion Guidance

Converting Between Medications

• To convert from Norco 10-325 (hydrocodone/acetaminophen) to Percocet, use approximately Percocet 7.5-325 mg at the same dosing interval 2
• Both medications contain the same amount of acetaminophen (325 mg) per tablet, so monitor total daily acetaminophen dose to avoid exceeding 3000-4000 mg/day 2
• When converting between opioids, start with the calculated equivalent dose but be prepared to adjust based on individual patient response 2

Clinical Bottom Line

While hydrocodone and oxycodone are both effective opioid analgesics that provide similar pain relief at equianalgesic doses, they are distinctly different medications with different risk profiles. With a goal of reducing overdose-related deaths, hydrocodone may be the more favorable agent 4, though it carries higher risk for transition to long-term use 3. The choice between them should account for these different safety profiles, with oxycodone reserved for situations where its higher potency is specifically needed, and hydrocodone preferred when minimizing overdose risk is the priority.