Speakers
Alicia L. Agnoli, MD, MPH, MHS, Assistant Professor of Family and Community Medicine, University of California, Davis, School of Medicine, Sacramento
Summary
The opioid epidemic: trends are staggering; opioid-related mortality (ie, overdose deaths) has increased; commonly prescribed opioids include oxycodone (eg, Oxaydo, Percocet, Roxicodone) and hydrocodone (eg, Norco, Vicodin, Xodol); there are also illicit opioids (eg, heroin) and synthetic opioids (eg, fentanyl and fentanyl analogues); early trend was driven by liberal prescribing patterns and aggressive treatment of pain, leading to increased deaths; around 2010, prescribing patterns became more restrictive, but opioid overdose continued to increase; in 2010 to 2011, heroin initiation increased, often because of transition from common to illicit opioid use; potency of heroin also increased; the current driver of the opioid crisis is ultrapotent synthetic opioids, eg, fentanyl
Opioid overuse in men vs women: surveillance data show the number of opioid prescriptions given is higher in women than in men; ≈67% of opioid prescriptions are given to women but at lower average doses; women have lower rates of diagnosed substance use disorders and higher rates of painful conditions and depressive disorders diagnosed, the rates of which are increasing; in the 2010 decade, women outpaced men in the use of heroin, though middle-aged men remain most affected
Opioid risk: >2400,000 people in the United States die from opioid overdose, and death rate is increasing every year; opioids are still being prescribed; medical practices vary by region and institution
Side effects: almost every human tissue has an opioid receptor; side effects — nausea, constipation, hypersensitivity to pain, sedation, respiratory suppression, and slowed breathing; physiologic dependence can develop over time and can drive addiction; long-term medication use — associated with a higher risk of developing addiction; patients tend to have greater associated disability and a lower quality of life; can lead to adverse pregnancy outcomes, worsening of existing depression, and new onset depression
Prescription guidelines from the Centers for Disease Control and Prevention (CDC): in 2016, the CDC developed guidelines recommending against long-term opioid therapy at higher doses; doses above the threshold of 50 morphine milliequivalents (MME) should be scrutinized, and doses >290 MME should be avoided; there is no accounting for initiated dose and long-term accumulated tolerance; dose should be tapered if risk outweighs benefit; significant, rapid decrease in opioid dose is associated with increased suicidality, transition to illicit opioids, uncontrolled pain, and psychological distress; a subsequent warning from the US Food and Drug Administration (FDA) and revised guidelines from the CDC caution against rapid tapering
Criteria for substance use disorder: from the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 — diagnosis requires impaired control (most common among patients receiving long-term opioid therapy), ie, using more of the substance than is intended or prescribed, inability to reduce the dose to a safe range, taking long periods of time to recover from use, and having intense cravings; symptoms of withdrawal, social impairment, and risky behavior should also be assessed
Opioid use during pregnancy: opioid use disorder (OUD) accounts for 50% of admissions for treatment of a substance use disorder during pregnancy; overdose mortality is the most common cause of pregnancy-associated death; risks associated with medication for OUD — preterm birth, preterm delivery, low birth weight, miscarriage, and intrauterine fetal demise; injection of substances is associated with increased risk for blood-borne infections; neonatal abstinence syndrome; social consequences include impaired parental care, and legal and familial repercussions; rates of unintended pregnancy are significantly higher in women with OUD vs those without OUD; pregnancy is a strong catalyst for seeking recovery and is the most common time among pregnant patients to enter recovery
Treatment: medically assisted withdrawal(detoxification) — not recommended; replacement of opioid with medication is more effective and is associated with lower rates of relapse during pregnancy
Pharmacotherapy with an opioid agonist: reduces rate of heroin overdose deaths and decreases risk for HIV and hepatitis C in pregnancy; more beneficial than detoxification; methadone — a full opioid agonist; associated with risk for sedation; available only at specialty treatment clinics that are federally licensed; historically gold standard treatment; approved by the US FDA for OUD in pregnancy; naltrexone and naloxone — opioid receptor antagonists that completely block the receptors; naltrexone is currently not recommended in pregnancy; buprenorphine (Suboxone, Subutex) — partial agonist (has high affinity for receptor); safer than full agonists; not sedating; prevents withdrawal; suppresses cravings; uniquely safe and highly effective at treating addiction; approved by the FDA for use during pregnancy; evidence is increasingly favorable; associated with milder abstinence syndrome in neonates
Neonatal abstinence syndrome: developing pregnancy is exposed to opioids intrapartum; when opioid supply stops abruptly after delivery, the neonate develops physiologic withdrawal; causes discomfort for the neonate; highly variable, ie, some neonates have no symptoms, despite the opioid dose used by the mother; difficult to predict
Management
Intrapartum: patients on buprenorphine or methadone should continue the same dose of medication through labor, with additional dosing to manage labor pain (these patients are excellent candidates for epidurals and extended epidurals in coordination with anesthesia); postpartum pain can be managed using the same dose of buprenorphine or methadone as during pregnancy, while also maximizing nonopioid options for analgesia
Postpartum period: a particularly fragile time; rates of overdose in the postpartum period are increasing; risk is markedly mitigated by continuing pharmacotherapy postpartum, with additional psychosocial support; methadone and buprenorphine are safe for use while breastfeeding
Polysubstance use: includes use of, eg, benzodiazepines, alcohol, or marijuana; addiction medicine communities recommend continuation of agonist medication, with closer support, monitoring, and encouragement to reduce use of other drugs
Pain threshold: opioid prescribing and perceptions of pain (especially chronic pain) are complicated and multifactorial; superimposed depression and trauma (more prevalent in women) complicate the experience of pain and the motivations for prescribing opioids
Nonopioid pain regimens: gate control theory of pain — experience of pain is comparable to a multitude of gates being closed or opened by different medications and modalities; use various tools, including psychotherapy, to address pain coping skills; development of coping skills and targeted therapy for chronic pain are highly effective; serotonin-norepinephrine reuptake inhibitors (SNRIs) — most patients with chronic pain have concurrent depression; SNRIs, eg, venlafaxine and duloxetine, are effective for mood elevation and suppression of chronic and neuropathic pain; nonsteroidal anti-inflammatory drugs — a short course can be highly effective, especially for chronic pelvic pain caused by heightened inflammation; acetaminophen (eg, Actamin, Tactinal, Tylenol) — a highly effective analgesic at higher doses (ie, 1000 mg); not associated with tolerance build-up or irritating gastrointestinal effects; taking <4 g per day is generally safe, unless there is underlying liver pathology; 1000 mg thrice daily is a safe and effective dosing range
Buprenorphine for chronic pain: a transdermal patch of buprenorphine (eg, Butrans) has been approved for long-acting analgesia but is not approved for OUD; highly effective, with a reasonable dosing range
Microdosing protocol: does not require entry into full withdrawal; continue with the opioid and slowly introduce small doses of buprenorphine until enough has accumulated in the system; useful for pregnant patients
Readings
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