What is the recommended dosing for oxycodone (OxyContin) and Percocet (oxycodone and acetaminophen) for a patient with moderate to severe pain, considering factors such as age, weight, and medical history, including impaired renal or hepatic function?

Oxycodone and Percocet Dosing for Pain Management

Immediate-Release Oxycodone (Without Acetaminophen)

For moderate to severe pain, start with oxycodone 5-10 mg orally every 4-6 hours as needed, titrating upward based on response. 1

• Opioid-naive patients should begin at 5 mg every 4-6 hours as needed to minimize respiratory depression risk 2
• For severe pain requiring urgent relief, doses up to 15 mg may be used, though this carries higher adverse event risk 3
• Prescribe "as needed" rather than scheduled dosing to minimize total opioid exposure 4
• Limit duration to 3-5 days for acute pain conditions 4

Dose Titration Strategy

• Provide breakthrough doses equivalent to 10% of total daily dose for transient pain exacerbations 1
• If more than 4 breakthrough doses per day are needed, increase the baseline dose 1
• Titrate doses rapidly to effect while monitoring for respiratory depression 1

Percocet (Oxycodone/Acetaminophen Combination)

For moderate to severe acute pain, prescribe oxycodone 5 mg/acetaminophen 325 mg, 1-2 tablets every 4-6 hours as needed, not exceeding 6 doses in 24 hours. 4, 5

Standard Dosing Regimens

• The most effective combination is oxycodone 10 mg plus acetaminophen 650 mg, which provides good analgesia to approximately 50% of patients with a duration of 10 hours 3
• Lower doses (oxycodone 5 mg/acetaminophen 325 mg) provide 4 hours of pain relief 3
• 97% of patients achieving pain relief required only 1.61 ± 0.67 doses of oxycodone 5 mg combined with 325 mg acetaminophen 5
• The combination has a number-needed-to-treat (NNT) of 2.7 for at least 50% pain relief over 4-6 hours 3

Critical Acetaminophen Safety Limits

• Never exceed 4000 mg acetaminophen daily from all sources combined 4, 2
• Explicitly counsel patients to avoid all other acetaminophen-containing products (cold medications, other pain relievers) as hidden acetaminophen is a major cause of unintentional overdose 4
• Reduce maximum daily acetaminophen to 2000-3000 mg in patients with hepatic impairment 4
• For elderly patients (≥65 years), limit acetaminophen to 3000 mg daily 4

Special Population Dosing Adjustments

Elderly Patients (≥65 Years)

• Start at the low end of the dosing range (oxycodone 5 mg or oxycodone 5 mg/acetaminophen 325 mg) 2
• Elderly patients have increased sensitivity to oxycodone and higher risk of respiratory depression 2
• Titrate slowly and monitor closely for central nervous system and respiratory depression 2

Hepatic Impairment

• Initiate therapy with lower than usual dosages and titrate carefully due to decreased oxycodone clearance 2
• Monitor closely for respiratory depression, sedation, and hypotension 2
• Reduce maximum acetaminophen to 2000-3000 mg daily and monitor liver enzymes 4

Renal Impairment

• Start with lower than usual dosages and extend dosing intervals as oxycodone is substantially excreted by the kidney 2
• Consider dose reduction or extended intervals due to altered codeine metabolism 4
• Monitor closely for respiratory depression, sedation, and hypotension 2

Alternative First-Line Strategy Before Opioids

Consider ibuprofen 400-600 mg every 6 hours as first-line treatment before escalating to opioid combinations, as it may be equally or more effective for many acute pain conditions. 4, 6

• Ibuprofen 400 mg alone has comparable efficacy to oxycodone/acetaminophen combinations for certain acute pain types 4
• For moderate pain, start with acetaminophen up to 4000 mg daily before adding opioids 6
• Reserve opioid combinations for patients who fail NSAIDs or acetaminophen alone 1

Comparative Efficacy: Oxycodone vs. Percocet

The fixed-dose combination of oxycodone with acetaminophen provides superior analgesia compared to either agent alone due to synergistic mechanisms of action. 7, 3

• Oxycodone 10 mg plus acetaminophen 650 mg is comparable to commonly used NSAIDs but with longer duration of action (10 hours vs. 4-6 hours) 3
• The combination allows lower individual drug doses, reducing adverse effects while maintaining efficacy 7, 8
• Oxycodone is 2-3 times stronger than codeine on a milligram-per-milligram basis 3

Critical Safety Warnings and Monitoring

Respiratory Depression Risk

• Respiratory depression is the chief risk, especially in opioid-naive patients, elderly patients, and when combined with other CNS depressants 2
• Avoid large initial doses in opioid-naive patients 2
• Monitor closely when co-administering with benzodiazepines, alcohol, or other sedating medications 2

Duration Limits

• Limit use to the shortest duration necessary, typically 3-5 days for acute pain 4
• Reassess if pain persists beyond 5-7 days and consider alternative diagnoses or multimodal approaches 4
• Avoid scheduled dosing; prescribe "as needed" to minimize total opioid exposure 4

Common Pitfalls to Avoid

• Failure to account for acetaminophen in combination products when patients are taking other acetaminophen-containing medications 4
• Starting with excessively high doses in opioid-naive or elderly patients 2
• Prescribing scheduled dosing rather than "as needed" for acute pain 4
• Inadequate counseling about avoiding alcohol and other CNS depressants 2

Practical Prescribing Algorithm

1. Assess pain severity and prior analgesic use:

   • Mild-moderate pain: Start with acetaminophen or NSAIDs 1, 6
   • Moderate-severe pain in NSAID failures: Oxycodone 5 mg/acetaminophen 325 mg 4, 5
   • Severe pain: Oxycodone 10 mg/acetaminophen 650 mg 3

2. Screen for contraindications:

   • Hepatic impairment: Reduce acetaminophen maximum 4, 2
   • Renal impairment: Reduce oxycodone dose and extend intervals 2
   • Elderly (≥65 years): Start low, go slow 2
   • Respiratory disease: Use extreme caution or avoid 2

3. Prescribe appropriately:

   • Write for "as needed" dosing, not scheduled 4
   • Limit quantity to 3-5 days supply 4
   • Provide explicit acetaminophen warning 4

4. Provide breakthrough dosing:

   • Breakthrough dose = 10% of total daily dose 1
   • If >4 breakthrough doses needed daily, increase baseline 1