Adult Dosing
Opioid Dependence (treatment in accordance with the treatment standards cited in the Code of Federal Regulation, Title 42, Section 8.12)
Detoxification
- Start 20-30 mg PO x 1, evaluate after 2-4 hrs. May give additional 5-10 mg if withdrawl symptoms have not subsided
- Max: 40 mg on day 1
- Adjust dose over the first wk of therapy based on control of withdrawl symptoms at the time of expected peak activity (2-4 hrs after dosing)
Short term detoxification
- Start: 15-30 mg PO x 1, evaluate after 2-4 hrs. May give additional 5-10 mg if withdrawl symptoms have not subsided
- Max: 40 mg on day 1
- Adjust dose to suppress withdrawal symptoms; stabilize dose x 2-3 days, then decrease dose by up to 20% q24-48 hrs
Maintenence therapy
- 80-120 mg/day PO; titrate to a dose at which opioid symptoms are prevented for 24 hrs, drug hunger or craving is reduced and the euphoric effects of self administered opioids are blocked or attenuated
Medically supervised withdrawal (after a period of maintenance treatment)
- Reduce dose by less than 10% (of the established tolerance or maintenence dose) q10-14 days
Pain, moderate to severe
Opioid nontolerant patients
- Start: 2.5-10 mg PO q8-12 hrs, titrate slowly to effect
Opioid tolerant patients
- Conversion from parentral methadone to oral methadone: follow a 1:2 dose ratio (eg 5 mg parentral methadone to 10 mg oral methadone)
- Conversion from other chronic opioids: As per the following guidelines
Total daily baseline
ORAL morphine dose | Estimated daily ORAL
methadone requirement
(% of total daily morphine dose) |
|---|
| <100 mg | 20-30% |
| 100-300 mg | 10-20% |
| 300-600 mg | 8-12 % |
| 600-1000 mg | 5-10 % |
| > 1000 mg | < 5% |
:
- Particular vigilance is required while converting from other opioids
- Conversion ratios using euianalgesic dosing tables do not apply in the setting of repeated methadone dosing
Pediatric Dosing
- Safety and effectiveness in pediatric patients (<18 years of age) has not been established
[Outline]
See Supplemental Patient Information
- Schedule II controlled substance; significant potential for abuse liability similar to other opioid agonists, legal or illicit. Evaluate patient’s risk for opioid abuse or addiction before administrating methadone. Patients at increased risk for abuse are those with a personal or family history of substance abuse or mental illness. Monitor patients for signs of misuse, abuse, addiction during treatment (FDA Black Boxed warning)
- Carbon dioxide (CO2) retention from opioid-induced respiratory depression can worsen the sedating effects of opioids. Patient with respiratory depression should be closely monitored and managed with supportive measures, including use of opioid antagonists
- Methadone peak respiratory depressant effects typically occur later and last longer than peak analgesic effects; particular during the initial dosing period (FDA Black Boxed warning)
- QT prolongation and serious arrhythmias including torsades de pointes have been occurred during treatment with methadone. Closely evaluate patients having risk of prolonged QT interval (hypertrophy, concomitant diuretic use, hypokalemia, hypomagnesemia) and in patients with history of cardiac conduction abnormalities
- Accidental exposure of therapy, particularly in children, may result in a fatal overdose of methadone
- Elderly, cachectic, debilitated patients and patients with chronic pulmonary disease or cor pulmonale are at greater risk of respiratory depression and should be monitor closely, especially when initiating and titrating methadone and when given concomitantly with other drugs that depress respiration. Use methadone cautiously in conditions accompanied by hypoxia, hypercapnia, or decreased respiratory reserve
- Hypotension, profound sedation, coma, or respiratory depression may occur when used concomitantly with CNS depressants. Consider the use of therapy in a patient taking a CNS depressant or use of substances such as alcohol or illicit drugs
- Severe hypotension including orthostatic hypotension and syncope in ambulatory patients may occur in patients whose ability to maintain normal BP is compromised (eg, severe volume depletion)
- Avoid methadone in patients with gastrointestinal obstruction. Therapy may cause spasm of the sphincter of Oddi. Closely monitor patients with biliary tract disease, including acute pancreatitis, for worsening symptoms
- Taper slowly to discontinue. Physical dependence manifested by withdrawal symptoms and/or seizures may occur after abrupt discontinuation or administration of an antagonist
- May need to decrease dose in patients with hepatic/renal impairment
- A high degree of "opioid tolerance" does not eliminate the possibility of methadone overdose, iatrogenic or otherwise
- Monitor continuously for recurrence of respiratory depression; may need treatment with the narcotic antagonist
- May impair ability to drive or operate machinery
- Monitor Cr at baseline
Cautions: Use cautiously in
- Renal impairment
- Hepatic impairment
- Impaired pulmonary function (asthma, COPD)
- Severe obesity
- Sleep apnea syndrome
- Myxedema
- Cardiac conduction defects
- QT prolongation
- Cardiac hypertrophy
- Concurrent diuretics
- Head trauma
- Thyroid disorder
- Concomitant diuretic use
- Hypokalemia
- Hypomagnesemia
- Increased intracranial pressure
- Alcohol/drug abuse
- CNS depression
- Coma
- Undiagnosed acute abdominal pain
- Prostatic hypertrophy
- Addisons disease
- Urethral stricture
- Biliary disease
- Geriatric population
Supplemental Patient Information
- Avoid sudden cessation, always reduce the dose prior to discontinuation
Pregnancy Category:C
Breastfeeding: Methadone is excreted in breast milk. When used as maternal maintenance therapy, breastfeeding may decrease neonatal withdrawal symptoms in infants who were exposed in utero. However, it is excreted in only small amounts, a breastfed infant may require treatment for withdrawal. Initiation of methadone postpartum, or increasing the maternal dosage to > 100 mg/day therapeutically or by abuse, subjects the infant to a greater risk of sedation and respiratory depression. Monitor infant for signs of increased sedation, breathing difficulties, or limpness. This information is based upon LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT). This drug is considered compatible with breastfeeding based upon data from from AAP Policy Guidelines (available at http://aappolicy.aappublications.org/cgi/content/full/pediatrics;108/3/776 last accessed 22 July 2010)
Pricing data from www.DrugStore.com in U.S.A.
- Methadose 10 MG TABS [Bottle] (MALLINCKRODT PHARM)
20 mg = $13.99
30 mg = $18.99 - Methadone HCl 5 MG TABS [Bottle] (ROXANE)
20 mg = $11.99
30 mg = $17.99 - Methadone HCl 10 MG TABS [Bottle] (ROXANE)
20 mg = $11.99
30 mg = $16.99
Warning: This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.
