The following serious adverse reactions are discussed elsewhere in the labeling:
- Addiction, Abuse, and Misuse [see WARNINGS AND PRECAUTIONS]
- Life Threatening Respiratory Depression [see WARNINGS AND PRECAUTIONS]
- QT Prolongation [see WARNINGS AND PRECAUTIONS]
- Neonatal Opioid Withdrawal Syndrome [see WARNINGS AND PRECAUTIONS]
- Interactions with Other CNS Depressants [see WARNINGS AND PRECAUTIONS]
- Hypotensive Effect [see WARNINGS AND PRECAUTIONS]
- Gastrointestinal Effects [see WARNINGS AND PRECAUTIONS]
- Seizures [see WARNINGS AND PRECAUTIONS]
The major hazards of methadone are respiratory depression and, to a lesser degree, systemic hypotension. Respiratory arrest, shock, cardiac arrest, and death have occurred.
The most frequently observed adverse reactions include lightheadedness, dizziness, sedation, nausea, vomiting, and sweating. These effects seem to be more prominent in ambulatory patients and in those who are not suffering severe pain. In such individuals, lower doses are advisable.
Other adverse reactions include the following:
Body as a Whole: asthenia (weakness), edema, headache
Cardiovascular: arrhythmias, bigeminal rhythms, bradycardia, cardiomyopathy, ECG abnormalities, extrasystoles, flushing, heart failure, hypotension, palpitations, phlebitis, QT interval prolongation, syncope, T-wave inversion, tachycardia, torsades de pointes, ventricular fibrillation, ventricular tachycardia
Central Nervous System: agitation, confusion, disorientation, dysphoria, euphoria, insomnia, hallucinations, seizures, visual disturbances
Gastrointestinal: abdominal pain, anorexia, biliary tract spasm, constipation, dry mouth, glossitis
Hematologic: reversible thrombocytopenia has been described in opioid addicts with chronic hepatitis
Metabolic: hypokalemia, hypomagnesemia, weight gain
Renal: antidiuretic effect, urinary retention or hesitancy
Reproductive: amenorrhea, reduced libido and/or potency, reduced ejaculate volume, reduced seminal vesicle and prostate secretions, decreased sperm motility, abnormalities in sperm morphology
Respiratory: pulmonary edema, respiratory depression
Skin and Subcutaneous Tissue: pruritus, urticaria, other skin rashes, and rarely, hemorrhagic urticaria
Hypersensitivity: Anaphylaxis has been reported with ingredients contained in DOLOPHINE. Advise patients how to recognize such a reaction and when to seek medical attention.
Maintenance on a Stabilized Dose
During prolonged administration of methadone, as in a methadone maintenance treatment program, constipation and sweating often persist and hypogonadism, decreased serum testosterone and reproductive effects are thought to be related to chronic opioid use.
DOLOPHINE for the Detoxification and Maintenance Treatment of Opioid Dependence
During the induction phase of methadone maintenance treatment, patients are being withdrawn from illicit opioids and may have opioid withdrawal symptoms. Monitor patients for signs and symptoms including: lacrimation, rhinorrhea, sneezing, yawning, excessive perspiration, goose-flesh, fever, chilling alternating with flushing, restlessness, irritability, weakness, anxiety, depression, dilated pupils, tremors, tachycardia, abdominal cramps, body aches, involuntary twitching and kicking movements, anorexia, nausea, vomiting, diarrhea, intestinal spasms, and weight loss and consider dose adjustment as indicated.