Methadone

DEA Class; Rx

Common Brand Names; Methadose, Dolophine

A phenylheptylamine synthetic opiate agonist; is structurally unrelated to morphine
Used in medically supervised opiate withdrawal and maintenance programs; effective for the relief of severe or chronic pain

Hypersensitivity to methadone or formulation components; acute abdominal condition, toxin-mediated diarrhea, pseudomembranous colitis, respiratory depression; concurrent use of selegiline, hypercarbia, known or suspected gastrointestinal obstruction, including paralytic ileus, asthma (acute), significant respiratory impairment

Acute pain or postoperative pain; pain that is mild or not expected to persist

• Agitation
• Angina pectoris
• Anticholinergic effects (dry mouth, palpitation, tachycardia)
• Bradycardia
• Cardiac arrest
• Coma
• Constipation
• Dizziness
• Dysphoria
• Euphoria
• Faintness
• Mental clouding or depression
• Myocardial infarction
• Nausea
• Pruritus, urticaria
• Nervousness
• QT-interval prolongation
• Respiratory arrest
• Respiratory/circulatory depression
• Restlessness
• Sedation
• Seizures
• Severe cardiac arrhythmias
• Shock
• ST-segment elevation
• Sweating, flushing, warmness of face/neck/upper thorax
• Syncope
• Urinary retention, oliguria
• Ventricular tachycardia
• Visual disturbances
• Vomiting
• Weakness

Schedule II opioid analgesics expose users to the risks of addiction, abuse, and misuse; there is a greater risk for overdose and death with extended-release opioids due to the larger amount of active opioid present (see Black Box Warnings)

Opioids can cause sleep-related breathing disorders including central sleep apnea (CSA) and sleep-related hypoxemia; opioid use increases risk of CSA in a dose-dependent fashion; in patients who present with CSA, consider decreasing opioid dosage using best practices for opioid taper

Addiction, abuse, and misuse risks are increased in patients with a personal or family history of substance abuse or mental illness (eg, major depression); the potential for these risks should not, however, prevent the prescribing of proper pain management in any given patient; intensive monitoring is necessary (see Black Box Warnings)

Serious, life-threatening, or fatal respiratory depression reported (see Black Box Warnings)

May cause constipation, which could cause problems in patients with unstable angina and patients post-myocardial infarction; consider preventive measures (sool softener, increased fiber in diet) to reduce potential for constipation

Accidental exposure reported, including fatalities (see Black Box Warnings)

Do not abruptly discontinue buprenorphine in a patient physically dependent on opioids; when discontinuing therapy, in a physically dependent patient, gradually taper the dosage; rapid tapering in a patient physically dependent on opioids may lead to a withdrawal syndrome and return of pain

Neonatal opioid withdrawal syndrome reported with long-term use during pregnancy (see Black Box Warnings)

Interactions with CNS depressants (eg, alcohol, sedatives, anxiolytics, hypnotics, neuroleptics, other opioids) can cause additive effects and increase risk for respiratory depression, profound sedation, and hypotension; deaths reported due to methadone abuse in conjunction with benzodiazepines

There are no adequate and well-controlled studies in pregnant women; untreated opioid addiction is associated with adverse obstetrical outcomes such as low birth weight, preterm birth, and fetal death

Methadone present in low levels in human milk; did not show adverse reactions in breastfed infants