Presentation and Status in Health Basket
Adolan is intended for oral use only. The dosage range is 2.5-10mg every three to four hours as necessary. It is not recommended for use as an analgesic in children due to insufficient documentation.
Gastro-intestinal spasms, renal, biliary colic, neuralgia, gynecological pains, withdrawal treatment of morphine and pethidine addiction, relief of severe pain.
Known hypersensitivity to methadone or to any other ingredient of the preparation. Respiratory depression, obstructive airways disease (especially in the presence of cyanosis and excessive bronchial secretions) and during an acute asthma attack Patients dependent on non-opioid drugs Concurrent administration with monoamine oxidase inhibitors (including moclobemide) or within 2 weeks of discontinuation of them. Head injury and raised intracranial pressure (further rise in intracranial pressure–papillary response affected. Where there is a risk of paralytic ileus. In patients with ulcerative colitis, since it may precipitate toxic dilation or spasm of the colon. in patients with severe hepatic impairment as it may precipitate hepatic encephalopathy Acute alcoholism Use during labor (prolonged duration of action increases the risk of neonatal depression). in biliary and renal tract spasm Children (serious risk of toxicity).
Methadone may interfere with evaluation of CNS function, thereby masking the patient’s clinical course. Patients with reduced blood volume may be more sensitive to the hypotensive effects of methadone than other patients. The use of methadone in patients with chronic ulcerative colitis may stimulate motility in the colon; in patients with acute ulcerative colitis, toxic dilation may occur. Methadone induced increase in intraluminal pressure may endanger surgical anastomosis. Methadone may obscure the diagnosis or clinical course in patients with acute abdominal conditions. Plasma amylase and lipase determinations should not be performed within 24 hours after a methadone dose, which may increase the activity of these markers. Patients with prostatic hypertrophy or urethral stricture may be more prone to urinary retention and oliguria than other patients. Methadone may increase the risk of water intoxication in postoperative patients because of the stimulation of the release of vasopressin, suppression of gonadotrophic function may cause impotence and a decline in libido. Methadone may have a prolonged duration and cumulative effect in patients with hepatic or renal dysfunction.
Cardiac conduction effects : Laboratory studies, both in vitro and in vivo, have demonstrated that methadone inhibits cardiac potassium channels and prolongs the QT interval. Cases of QT interval prolongation and serious arrhythmia (torsades de pointes) have been observed during treatment with methadone. These cases appear to be more commonly associated with, but not limited to, higher dose treatment (>200 mg/day). Most cases involve patients being treated for pain with large, multiple daily doses of methadone although cases have been reported in patients receiving doses commonly used for maintenance treatment of opioid addiction. Methadone should be administered with particular caution to patients already at risk for development of prolonged QT interval (e.g. cardiac hypertrophy, concomitant diuretic use, hypokalaemia, hypomagnesaemeia). Careful monitoring is recommended when using methadone in patients with a history of cardiac conduction abnormalities, those taking medications affecting cardiac conduction, and in other cases where history or physical exam suggest an increased risk of dysrhythmia. QT prolongation has also been reported in patients with no prior cardiac history who have received high doses of methadone. Patients developing QT prolongation while on methadone treatment should be evaluated for the presence of modifiable risk factors, such as concomitant medications with cardiac effects, drugs which might cause electrolyte abnormalities, and drugs which might act as inhibitors of methadone metabolism. For use of methadone to treat pain, the risk of QT prolongation and development of dysrhythmias should be weighed against the benefit of adequate pain management and the availability of alternative therapies.
Drug Dependence: Methadone has abuse potential. Psychological dependence as well as physical tolerance and dependence may develop upon repeated use. Patients who receive methadone regularly for more than a few days may exhibit mild symptoms upon discontinuation. However, most patients who receive opiates for medical reasons do not develop dependence syndromes.
Asthma and Other Respiratory Conditions: Methadone should be used with extreme caution in patients with acute asthma,chronic obstructive pulmonary disease or cor pulmonale, a substantially decreased respiratory reserve, and with pre-existing respiratory depression, hypoxia or hypercapnia. Even therapeutic doses of narcotics may decrease respiratory drive while simultaneously increasing airway resistance to the point of apnea.
Hypotension: Hypotension may result in the postoperative patient or in any individual whose ability to maintain blood pressure is compromised by hypovolemia or concurrent administration of phenothiazines or general anesthetics. Narcotics may produce orthostatic hypotension in ambulatory patients.
Should be used with extreme caution in patients with acute asthma, chronic obstructive pulmonary disease or respiratory reserve, pregnancy and lactation, elderly and debilitated patients, pediatrics, sensitive to CNS depressants, cardiovascular disease, myxedema, acute alcoholism, delirium tremens, cerebral arteriosclerosis, fever, kyphoscoliosis, Addison’s disease, prostatic hypertrophy or urethral stricture, severe CNS depression or coma, atrial flutter and other supraventricular tachycardias, cough reflex is suppressed, driving a car or operating machinery.
For full details see prescribing information
Respiratory depression, circulatory depression, shock and cardiac arrest, lightheadedness, dizziness, sedation, nausea, vomiting and sweating, euphoria, dysphoria, delirium, headache, drowsiness, miosis, insomnia, agitation, tremor, impairment of mental and physical performance, lethargy, anxiety, fear, psychic dependence, mood changes, hallucinations, disorientation, confusion and visual disturbances, choreic movements, gastrointestinal changes, cardiovascular changes, ureteral, vesical sphincters spasm, allergic reactions, muscular rigidity.
For full details see prescribing information
Alcohol, Benzodiazepines, Buprenorphine, Carbamazepine, Chlormethiazole,
Cimetidine, Cisapride, domperidone, metoclopramide, Cyclizine and other
sedating antihistamines. For the full list see prescribing information.
NOTE: Those with hepatitis C may have impaired liver function. This needs to be taken into account when the use of drugs metabolised by the liver is considered. The dose of paracetamol, for example, needs to be well within the standard 4 g per day.
For full details see prescribing information.
Pregnancy and Lactation
Pregnancy: There is no or inadequate evidence of safety in human pregnancy, but the drug has been widely used for many years without apparent ill consequence and animal studies have not shown any hazard. Methadone should only be used in pregnancy if the physician considers that the potential benefits outweigh the risks. It should be used cautiously under the close supervision of a physician if the physician considers it essential to continue or initiate (in the case of an i.v. opioid user) methadone maintenance. It may be necessary to increase the dose of methadone if withdrawal symptoms develop as increased clearance and reduced plasma levels have been reported during pregnancy.
Infants of methadone-maintained mothers may experience symptoms of withdrawal in utero and following birth. Methadone should not be used during labor as the prolonged duration of action increases the risk of neonatal depression.
Lactation: Methadone enters breast milk in concentrations approaching plasma levels (range 0.17-5.6 mcg/ml) and may present withdrawal symptoms in addicted infants. A decision must be made whether to discontinue breastfeeding or discontinue the methadone therapy.
Use in Pediatrics: The fatal dose of methadone in children is 10 – 20 mg. Symptoms of opioid overdose in children are similar to those in adults, with pupillary miosis; however, the pupils may be normoreactive or, rarely, fixed and dilated. Infants may have drowsiness, coma and apnoea. Children are usually, but not always, symptomatic. Known or suspected methadone-intoxicated children should be hospitalised, since respiratory depression may be observed as long as 48 hours after ingestion. Successful resuscitation with a narcotic antagonist may be followed by relapse. Treatment must include establishment of an airway, maintenance of adequate respiratory ventilation, precise supportive care to maintain fluid and electrolyte balance, naloxone, emptying of upper and lower gastrointestinal tracts, and prevention of aspiration of gastric contents.
Manifestations: Overdose of methadone is characterised by respiratory depression (a decrease in respiratory rate and/ortidal volume, Cheyne-Stokes respiration, cyanosis), pulmonary oedema, extreme somnolence, progressing to stupor or coma, maximally constricted pupils, skeletal muscle flaccidity, cold and clammy skin, and sometimes bradycardia and hypotension. The presence and signs of drug abuse supports the diagnosis. In children, methadone overdose produces drowsiness, floppiness, constricted pupils and apnoea. In severe overdose, particularly by the intravenous route, apnoea, circulatory collapse, cardiac arrest and death mayoccur.
Treatment: If ingestion is recent, gastric aspiration and lavage can be employed after acute poisoning.
Primary attention should be given to the re-establishment of adequate respiratory exchange through provision of a patent airway and institution of assisted or controlled ventilation. Narcotic antagonists can be used to counteract the potentially lethal respiratory depression in a non-tolerant individual, especially a child. Methadone is, however, a long acting depressant (36-48 hours) whereas the antagonists act for much shorter periods (1-3 hours). The patient must, therefore, be monitored continuously for recurrence of respiratory depression and treated repeatedly with the narcotic antagonist as needed. If the respiratory depression is only due to overdose with methadone, the use of other respiratory stimulants is not indicated. An antagonist should not be administered in the absence of clinically significant respiratory or cardiovascular depression. Intravenously administered narcotic antagonists (naloxone, nalorphine or levallorphan) can be used to reverse signs of intoxication and should be given repeatedly until the patient’s status remains satisfactory. Oxygen, intravenous fluids, vasopressors and other supportive measures should be employed as indicated. In an individual physically dependent on narcotics, the administration of the usual dose of a narcotic antagonist will precipitate an acute withdrawal syndrome. The severity of this syndrome will depend on the degree of physical dependence and the dose of the antagonist administered. The use of a narcotic antagonist in such a person should be avoided if possible. If it must be used to treat serious respiratory depression in the physically dependent patient, the antagonist should be administered with extreme care and by titration with smaller than usual doses of the antagonist. Patients should be monitored for signs of relapse for at least 48 hours.