What are the recommended dosages for hydrocodone and morphine (opioids) for pain management?

Recommended Dosages for Hydrocodone and Morphine

For hydrocodone, start with 5-10 mg orally every 4-6 hours as needed (maximum 60 mg/day), and for morphine, start with 15-30 mg orally every 4 hours as needed in opioid-naive patients. 1, 2

Hydrocodone Dosing

Initial Dosing for Opioid-Naive Patients

• Start with hydrocodone 5 mg/acetaminophen 325 mg: 1-2 tablets every 4-6 hours as needed, not exceeding 8 tablets daily 2, 3
• For hydrocodone 7.5 mg/acetaminophen 325 mg: 1 tablet every 4-6 hours as needed, maximum 6 tablets daily 2
• For hydrocodone 10 mg/acetaminophen 325 mg: 1 tablet every 4-6 hours as needed, maximum 6 tablets daily 2

Key Prescribing Principles

• Prescribe as "as needed" rather than scheduled dosing to minimize exposure and risk 3
• Use the lowest effective dose for the shortest duration consistent with treatment goals 2, 4
• Hydrocodone has a morphine milligram equivalent (MME) conversion factor of 1.0 4

Critical Acetaminophen Considerations

• Monitor total daily acetaminophen intake from all sources to avoid exceeding 4000 mg/day and prevent hepatotoxicity 3
• When prescribing 8 tablets of hydrocodone 5 mg/acetaminophen 325 mg daily, total acetaminophen reaches 2600 mg 2

Morphine Dosing

Initial Dosing for Opioid-Naive Patients

• Start with immediate-release morphine 15-30 mg orally every 4 hours as needed 1
• For patients older than 70 years, consider starting at 10 mg orally 5
• Morphine has a morphine milligram equivalent (MME) conversion factor of 1.0 4

Parenteral to Oral Conversion

• 3-6 mg of oral morphine is required to provide analgesia equivalent to 1 mg of parenteral morphine 1
• IV/subcutaneous morphine is approximately 3 times more potent than oral morphine due to first-pass metabolism 4, 6

Titration Strategy

• Titrate doses gradually using immediate-release formulations until pain is controlled 1, 7
• Once stable dosing is achieved with immediate-release morphine, conversion to extended-release formulations can be considered 1
• The same total daily dose of morphine can be used when converting from immediate-release to extended-release, but close monitoring for excessive sedation is essential 1

Morphine Milligram Equivalent (MME) Thresholds

Risk Stratification by Total Daily MME

• Up to 40 MME/day: Low dose 8
• 41-90 MME/day: Moderate dose 8
• ≥91 MME/day: High dose 8

Critical Dosing Thresholds

• At ≥50 MME/day, pause and carefully reassess individual benefits versus risks before any further dose increases 4
• Many patients do not experience additional benefit in pain or function from increasing doses to ≥50 MME/day, but face progressively increasing risks 4
• Beyond 90 MME/day, monitor carefully for respiratory depression and other adverse effects 6

Monitoring and Safety

Respiratory Depression Monitoring

• Monitor patients closely for respiratory depression, especially within the first 24-72 hours of initiating therapy and following any dosage increases 1, 2
• Hydromorphone and other potent opioids carry significant risk for respiratory depression, particularly with IV administration 6

Adherence and Abuse Prevention

• Implement urine drug testing from initiation and throughout therapy to identify non-compliance or illicit drug use 8
• Utilize prescription drug monitoring programs to identify doctor shopping and reduce prescription drug abuse 8
• Use opioid treatment agreements to reduce overuse, misuse, abuse, and diversion 8

Side Effect Management

• Initiate a bowel regimen (laxatives) as soon as opioid therapy begins to prevent constipation 4, 3
• Consider prescribing antiemetics for nausea if needed 4

Common Pitfalls to Avoid

• Do not use opioids as first-line therapy when nonopioid alternatives (NSAIDs, acetaminophen) may be effective for conditions like low back pain, neck pain, musculoskeletal injuries, minor surgeries, dental pain, kidney stones, or headaches 3
• Avoid scheduled around-the-clock dosing for acute pain; prescribe as-needed instead 3
• Do not convert directly to extended-release formulations in opioid-naive patients—titrate with immediate-release first 1, 7
• Never use MME calculations for direct opioid rotation—these are for risk assessment only; actual conversion requires 25-50% dose reduction due to incomplete cross-tolerance 4, 6
• Avoid abrupt discontinuation in patients on opioids for more than a few days—taper to prevent withdrawal symptoms 2
• Do not prescribe methadone without specific training in its risks and uses, and obtain baseline and follow-up ECGs 8

Special Populations

• For elderly patients or those with hepatic/renal impairment, start with lower doses and titrate cautiously 3
• In renal impairment, use reduced doses and extended dosing intervals 4