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Safe Opioid Prescribing

Prescription pad and pen

Opioid equivalency is an imperfect science due to variability in the chemical properties of analgesic drugs and each particular patient's response to those drugs. Equivalent doses of opioid analgesics are frequently calculated with respect to oral morphine equivalents. In addition to offering guidelines on the safe use of opioids, the Washington State Agency Medical Directors Group provides a useful table (adapted below) as well as an online calculator for calculating morphine equivalent dosage (MED). Clinicians should use caution when prescribing opioids at any dosage, should carefully reassess evidence of individual benefits and risks when considering increasing dosage to greater than or equal to 50 mg MEDs and should avoid increasing dosage to greater than or equal to 90 mg MEDs or carefully justify a decision to titrate dosage to ≥90 MME/day. When treating patients that exceed these thresholds providers should clearly document risk vs benefit, improvement in patient functional status, and applicable monitoring parameters.

Safe Opioid Prescribing:

  • Relies on the knowledge and skills of clinicians about the risks and benefits of opioid therapy
    • Risks: addiction, abuse, and diversion
    • Benefits: comfort, function, and quality of life
  • Complies with state and federal statutes
  • Fulfills responsibilities to patients, communities, and licensing authorities
Opioid Approximate Equianalgesic Dose (oral & transdermal)
Morphine (reference) 30mg
Codeine 200mg
Fentanyl transdermal 12.5mcg/hr
Hydrocodone 30mg
Hydromorphone 7.5mg
Oxycodone 20mg
Oxymorphone 10mg

Due to the unique properties of methadone, conversion between it and other opioids is particularly challenging. It is recommended that prescription of methadone be reserved for prescribers who specialize in pain management and/or are familiar with methadone. Many dosing tables may underestimate the potency of methadone. The analgesic effects of methadone are much greater with repeated dosing compared to one-time administration. The Department of Veterans Affairs and Department of Defense offer useful guidelines on the dosing of methadone.

When converting between opioids, prescribers and patients should be aware of the likelihood of incomplete cross tolerance. This term describes the phenomenon by which a patient's tolerance to one opioid agent may be markedly different from another agent, even at equianalgesic doses. Consequently, patients may be at increased risk for side effects and/or overdose when converting from one agent to another. It is generally recommended that prescribers account for incomplete cross tolerance when switching agents. This may be accomplished by scheduling the new agent at a dose 25-50% lower than the calculated equianalgesic dose with optional rescue doses provided in the event of uncontrolled or breakthrough pain.

Reducing Dose or Discontinuing Long-Term Opioid Therapy

Continuation, modification, or discontinuation of chronic opioid therapy should be contingent on the evaluation of the patient's progress toward treatment objectives and goals, risk of adverse events (including overdose or diversion), response to treatment, and quality of life. Whether or not opioids are continued, safe and effective nonopioid and/or non-pharmacologic treatments should be used in a patients' pain management plan based on an individualized assessment considering the diagnosis, access to treatment, and unique needs of the patient.

According to recent HHS recommendations, patients should be involved in the decision making and treatment planning process. Opioids should not be tapered rapidly or discontinued suddenly due to risk of significant opioid withdrawal. An individual care plan can be created with the patient to reduce risk of acute withdrawal, worsened pain syndrome, anxiety, depression, suicidal ideation, self-harm, weakened trust with the health system, and patients seeking opioids from illicit sources.

Hallmarks of a safely structured opioid discontinuation or tapering strategy include the following:

  • Patients on chronic opioid therapy who have become physically dependent should be provided with a safely structured individualized tapering regimen in addition to care coordination and alternate nonopioid and/or non-pharmacological treatment modalities as available.
  • Withdrawal should be managed by the provider or by referring the patient to a pain specialist. Oftentimes, slow or gradual tapers can lessen withdrawal symptoms
  • Intensive care coordination. The discontinuation of opioid treatment should not mark the end of treatment, but treatment should continue with other modalities, either through direct care or referral to other health care specialists.
  • Documentation of patient education that includes informing patients that there is an increased risk for overdose on abrupt return to a previously prescribed higher dose of opioids; documentation of education on an opioid overdose and offer naloxone where appropriate

Interdisciplinary case management is often helpful in the mutual decision to taper chronic opioid therapy. Engagement of pharmacists in care planning can help prescribers manage patient tapers, monitor response, manage withdrawal symptoms, and provide patient education. Behavioral health team members can assist with patient education and behavioral strategies surrounding anxiety with an opioid taper.

Consider tapering to a reduced opioid dosage, or tapering and discontinuing opioid therapy, when:

  • Pain improves
  • The patient receives treatment expected to improve pain
  • The patient requests dosage reduction or discontinuation
  • Pain and function are not meaningfully improved
  • The patient is receiving higher opioid doses without evidence of benefit from the higher dose
  • The patient has current evidence of opioid misuse
  • The patient experiences side effects that diminish quality of life or impair function
  • The patient experiences an overdose or other serious event (e.g., hospitalization, injury) or has warning signs for an impending event such as confusion, sedation, or slurred speech
  • The patient is receiving medications (e.g., benzodiazepines) or has medical conditions (e.g., lung disease, sleep apnea, liver disease, kidney disease, fall risk, advanced age) that increase risk for adverse outcomes
  • The patient has been treated with opioids for a prolonged period (e.g., years), and current benefit-harm balance is unclear

The HHS released guidance in September 2019 for Clinicians on the Appropriate Dosage Reduction or Discontinue of Long-Term Opioid Analgesics [PDF - 1.4 MB] Exit Disclaimer: You Are Leaving .

Drug Half-Life (T ½)
Estimated Clearance
(5 half-lives)
(Vicodin, Norco)
~8 hours ~40 hours
*Oxycodone IR
(Percocet, oxycodone)
~2-4 hours ~10-20 hours
*Oxycodone ER
~5 hours ~10 hours
(IR, MS Contin)
IR: ~2-4 hours
ER: ~11-13 hours
IR: ~10-40 hours
ER: ~55-65 hours
*Methadone ~8-59 hours ~40-295 hours/(2-13 days)
~37 hours ~185 hours/(8 days)

* Information adapted from UpToDate/Lexicomp®

The National Academy of Medicine Action Collaborative on Countering the U.S. Opioid Epidemic has posted the webinar recording and presenter slide decks from Tapering Guidance for Opioids: Existing Best Practices and Evidence Standards. Exit Disclaimer: You Are Leaving 


2022 CDC Clinical Practice Guideline for Prescribing Opioids for Pain Exit Disclaimer: You Are Leaving 

WA State Agency Medical Directors Group. Interagency Guideline on Opioid Dosing for Chronic Non-cancer Pain: An educational aid to improve care and safety with opioid therapy, 2010 Update Exit Disclaimer: You Are Leaving .

Department of Veterans Affairs/Department of Defense. Clinical practice guideline for management of opioid therapy for chronic pain. Exit Disclaimer: You Are Leaving  [PDF]

Webster LR, Fine PG. Overdose Deaths Demand a New Paradigm for Opioid Rotation. Pain Medicine. 2012; 13: 571-574

PL Detail-Document, Opioid Conversion Algorithm. Pharmacist's Letter/Prescriber's Letter. August 2012.