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Methadone Hydrochloride uses and description : Nurses PDR: Action/Kinetics: Produces only mild euphoria, which is the reason it is used as a heroin withdrawal substitute and for maintenance programs. Produces physical dependence; withdrawal symptoms develop more slowly and are less intense but more prolonged than those associated with morphine. Does not produce sedation or narcosis. Not effective for preoperative or obstetric anesthesia. Only one-half as potent PO as when given parenterally. Onset: 30-60 min. Peak effects: 30-60 min. Duration: 4-6 hr. t1/2: 15-30 hr. Both the duration and half-life increase with repeated use due to cumulative effects. Uses: Severe pain. Detoxification and maintenance of narcotic dependence."
http://www.nursespdr.com/members/database/ndrhtml/methadonehydrochloride.html ******************************************************

Methadone HCL Pharmacokenetics: University of Iowa Nursing: "Onset: Time frame depends on how supplied I.V. immediately I.M. 10 - 20 minutes Oral 30 - 60 minutes Epidural 5-10 minutes Peak Plasma Concentrations:IV 15 - 30 minutes IM 1 - 2 hours Oral 1 1/2 - 2 hours Oral dose is one half as potent as injected. Maximum benefit / side effect : 5 half lives Metabolism: Eliminated, primarily in renal system but small amount is biliary. Half Life:15 - 25 hours- increase with repeated administrations. Recent data suggests that the half life may be as long as 150 hours.Round the clock regimen may be necessary to manage severe chronic pain"
http://www.nursing.uiowa.edu/sites/adultpain/Narcs/methtt.htm ******************************************************

Methadone HCL effectively used for chronic pain control : Doctor's Guide: "Patients with chronic pain can be safely and effectively treated with methadone, researchers report.Forty patients who initially received methadone treatment at a university hospital pain clinic were followed and re-evaluated after two years. Patients who had maintained methadone use were compared to those who switched to other opioids.Fourteen patients (35 percent) stayed on methadone for the duration of the study. These patients had higher rates of employment and function compared with patients on other opioids."
http://www.docguide.com/news/content.nsf/news/A0E993687535D7478525699A005DDF41?OpenDocument&id=48DDE4A73E09A969852568880078C249&count=10&highlight=0,methadone

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Side effects of Methadone HCL : Walgreens Pharmacy: "Possible Side Effects: SIDE EFFECTS, that may go away during treatment, include drowsiness, dizziness, lightheadedness, nausea, vomiting, headache, or constipation. If they continue or are bothersome, check with your doctor. CHECK WITH YOUR DOCTOR AS SOON AS POSSIBLE if you experience excessive drowsiness, rash, itching, sweating, shortness of breath, or difficulty breathing. If you notice other effects not listed above, contact your doctor, nurse, or pharmacist."
http://www.walgreens.com/library/finddrug/druginfo.jhtml?_DARGS=%2Flibrary%2Ffinddrug%2Fdruginfo.jhtml.1_A&_DAV=8417 ******************************************************

Methadone HCL precautions : Inteli Health: "Over 60: Adverse reactions may be more likely and more severe in older patients. Driving and Hazardous WorkAvoid such activities until you determine how the medicine affects you. Avoid alcohol. Pregnancy: Adequate human studies have not been done. Before taking methadone, tell your doctor if you are pregnant or plan to become pregnant, and discuss the relative risks and benefits of methadone use during pregnancy. Breast Feeding: Methadone passes into breast milk; caution is advised. Taking large doses in a maintenance program can cause physical dependence in the baby. Consult your doctor for advice. Infants and Children: Adverse reactions may be more likely and more severe in children. Consult your doctor for advice. Special Concerns: If you feel the medication is not working properly after a few weeks, do not increase the dose. Consult your doctor. Before having any surgery, tell the doctor or dentist in charge that you are taking methadone."
http://www.intelihealth.com/IH/ihtIH?t=11624&p=~br,IPN|~st,8124|~r,WSIPN000|~b,*|#Infant

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Treatment for overdose of Methadone HC: Rx List: "Primary attention should be given to the reestablishment of adequate respiratory exchange through provision of a patent airway and institution of assisted or controlled ventilation. If a nontolerant person, especially a child, takes a large dose of methadone, effective narcotic antagonists are available to counteract the potentially lethal respiratory depression. The physician must remember, however, that methadone is a long-acting depressant (36 to 48 hours), whereas the antagonists act for much shorter periods (one to three hours). The patient must, therefore, be monitored continuously for recurrence of respiratory depression and treated repeatedly with the narcotic antagonist as needed. If the diagnosis is correct and respiratory depression is due only to overdosage of 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 naloxone is the drug of choice to reverse signs of intoxication. Because of the relatively short half-life of naloxone as compared with methadone, repeated injections may be required until the status of the patient remains satisfactory. Naloxone may also be administered by continuous intravenous infusion. Oxygen, intravenous fluids, vasopressors, and other supportive measures should be employed as indicated."
http://www.rxlist.com/cgi/generic/methdone_od.htm

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Test your knowledge of Methadone HCL with this quiz. Answers found here.: NAMA: "Pregnant women should withdraw or at least lower their dose of methadone so that the baby is not born dependent. True or false? Methadone gets into the bone marrow, rots the teeth, and "depletes calcium". True or false? Methadone suppresses the immune system so that HIV+ methadone patients should be encouraged to withdraw. True or false? If it is necessary for a methadone patient to take pain medication they do not need strong narcotics because the methadone will block the pain.? Answer Methadone causes patients to become alcoholics and/or cocaine abusers. True or false? Methadone is more addicting than heroin. True or false? Methadone patients should not be allowed to operate heavy machinery or to drive a car. True or false? Methadone was named for Adolph Hitler. True or false?When they do autopsies on methadone patients, the patients' internal organs are dyed bright orange. True or false?"
http://www.methadone.org/methadone_awareness_test.html

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Constipation is a big concern for Methadone patients.(Case study of Methadone HCL): American Family Physician: "Analgesia is often achieved with opioid treatment, but a common side effect is constipation. Because methylnaltrexone does not cross the blood-brain barrier, it does not antagonize the central nervous system effects of opioids but may decrease the peripheral effects of opioids. Yuan and colleagues studied the efficacy of methylnaltrexone, an opioid receptor antagonist, in the management of constipation associated with chronic methadone use.Twenty-two adults who had been in a methadone maintenance program for at least one month, who had a diagnosis of methadone-induced constipation and who were not currently using laxatives were included in the study. Patients with significant medical conditions or significant findings on physical examination were excluded. Patients continued to receive their normal dosage of methadone during the study. Oral-cecal transit time was measured. The morning after an overnight fast each participant received 10 g of lactulose and intravenous placebo (saline). In the evening, each subject received placebo or methylnaltrexone (up to 0.365 mg per kg) in four syringes."
http://www.findarticles.com/cf_dls/m3225/11_61/62829292/p1/article.jhtml