Methadone Research Paper

Methadone is a synthetic opioid, with long-acting action and can mimic the actions of morphine (Anderson & Kearney). It is primarily used for the treatment of opioid dependence, but can also be used as an analgesic (Brown, Kraus, Flemming, & Reddy), opioids can be considered to be depressant drugs due to the effects they have on the respiratory center. Methadone is a gamma-receptor agonist and may mimic the effect of endogenous opioids, enkephalins, and endorphins leading to effects such as euphoria, respiratory depression, sedation, increase in bowel activity, nausea, and miosis (Anderson & Kearney). Its analgesic effect has been attributed to the fact that it antagonizes N-methyl-D-aspartate receptors in the brain (Brown, Kraus, Flemming, & Reddy).

Mechanism of action

Methadone acts on opiate receptors which stimulate the exchange of Guanosine triphosphate for Guanosine diphosphate located on the G-protein complex. Opioids decrease intracellular cyclic adenosine monophosphate by inhibiting adenylate cyclase which then leads to the inhibition of nociceptive neurotransmitters like substance P, dopamine, acetylcholine, and noradrenaline. In recent years, the manufacturing of methadone is not tied down to a single manufacturer, but the active ingredient remains the same, methadone hydrochloride, 6-dimethylamino-4,4-diphenyl-3-heptanone  and is responsible for its attachment to the brain receptors (, furthermore, it allows its binding with plasma proteins (Brown, Kraus, Flemming, & Reddy). Methadone was manufactured by German Scientist just after the second world war, at a time when there was an epidemic of opioid addiction (Green, Kellogg, & Jeanne Kreek). The idea of the scientists was to produce a drug that could kill pain but not have the strong addictive property of morphine. By doing this, the scientists discovered the short-acting effects of morphine on the gamma receptors and modified another drug using morphine components that could alleviate pain and reduce addiction. Several German scientists were involved in the production of this drug during the second world war. By the end of the war, as requisitions, the United States obtained the rights for the drug and named it methadone in 1947. It was introduced into the United States as a pain reliever, but further along, it was discovered that it could be useful in treating narcotic addictions (Center for Substance Abuse Research).

Use of methadone

Methadone was initially manufactured for pain relief, but researchers eventually discovered its use in the treatment of opiate dependence. Methadone is a schedule 2 drug in the United States which means it is a drug that needs to be prescribed by a physician due to its high potential for abuse but it is can be found on the streets sold illicitly and has lead to a number of deaths from overdose (Center for Substance Abuse Research). Methadone is mainly used for maintenance therapy, detoxification, and pain and it is mainly administered orally.

Methadone Maintenance Therapy (MMT) is the long-term administration of methadone hydrochloride to patients with opiate dependency (Anderson & Kearney). The therapy helps replace the heroin with legally administered methadone; it helps the individual re-integrate into the society. Methadone therapy works by preventing heroin withdrawal symptoms; it blocks the euphoric effect of heroin thereby minimizing its craving, furthermore, due to its long-acting effect, abstinence syndrome associated with heroin is delayed (Anderson & Kearney). A 5mg dose of parenteral heroin is equivalent to a 10mg dose of methadone. Studies have shown that methadone maintenance therapy has been effective in decreasing the use of heroin and other substances, it has also shown to reduce the transmission of HIV, Hepatitis B, and C as well reduce criminal activity (Brown, Kraus, Flemming, & Reddy)

Detoxification by methadone involves short-term administration to block the abstinence symptom of heroin; the dose is then tapered to achieve full detoxification of the opiate-dependent patient (Anderson & Kearney). Detoxification doses usually start with 10-20mg and then increased by 10mg in order to control withdrawal symptoms. Methadone is primarily used for pain as it is well absorbed orally, has a long half-life and is not metabolized into any metabolites that may risk the life of the patient (Kearney & Anderson). Its use for treatment of chronic pain is not restricted. Therefore, it can be prescribed by any physician whose patient is not tolerating the analgesic effect of morphine; it can also be used for neuropathic pain treatment (Brown, Kraus, Flemming, & Reddy).  The effectiveness of methadone in the treatment of opiate dependent individuals as well as for chronic pain also has its negative impact. There are several side effects associated with the use of methadone, as it has been discussed, methadone has a long half-life reducing the pleasurable effects of heroin, but if administered wrongly it could also be addictive and present physical effects seen in heroin, even with its use in treating heroin dependents, methadone can also be abused.

Side-effects of Methadone

The short-term side effects of methadone could be due to the common side effects we get from everyday drugs; it could be due to administering too low dosage, it could be due to abuse of the drug. The common short-term effects of methadone include sweating, constipation, loss of appetite, nausea, vomiting, abdominal cramps, low sex drive, irregular periods, rashes, and itching. Side effects due to low dosage include a runny nose, and sneezing, backaches, joint aches, tears, irritability, and aggression, yawning, weakness, insomnia, and cravings for a drug of dependence (Kearney and Anderson). Effects due to abuse can be very severe. Most people who abuse methadone inject themselves with it which is not the proper route of methadone administration (Center for Substance Abuse Research). This leads to gaining infections of such diseases like HIV, and Hepatitis B. however, the most severe side effect of methadone abuse is central apnea, and this can lead to death. Central apnea arises from respiratory depression; methadone acts on the central opioid receptors reducing the hypercapnic and hypoxic states (Brown, Kraus, Flemming, & Reddy). Further symptoms that can arise from abuse include pinpoint pupils, hypotension, mental numbness, and coma. Research has also shown that methadone usage can also cause cholestatic liver damage. Long-term effects of methadone can include lung and respiratory diseases (CESAR).

Health Complications in Pregnant Women

In pregnant women,  methadone is not administered unless the woman is known to be opiate dependent. Research has shown that pregnant women on methadone deliver healthy and bigger children that women left without treatment from heroin dependence. Furthermore, sudden withdrawal of methadone during pregnancy should be avoided to prevent fetal death (The Pharmaceutical Journal). The advantages of maintaining methadone treatment during pregnancy include a more extended gestational period (Anderson & Kearney), spontaneous abortion can occur if methadone is withdrawn in the first trimester of a pregnant woman (The Pharmaceutical Journal). Methadone maintenance therapy, however, remains the standard of care for pregnant women with opioid dependence.

There is the belief that methadone is more addicting than heroin. A study showed that patients on methadone experience less severe withdrawal symptoms than people on heroin. However, if one is addicted to methadone, it is strongly adviced that he or she visits an addiction clinic because kicking the addiction alone could be worse due to the long-acting effect of the methadone. Furthermore, there is a myth that the name dolophine which was a brand name administered to methadone was gotten from Adolph Hitler, but the fact is that ‘dol’ was derived from the word ‘dolor’ meaning ‘pain.’

Works Cited

Anderson, I.B. and T.E. Kearney. “Use of methadone” Western journal of medicine vol. 172,1 (2000): 43-6.

Brown, Randall, et al. “Methadone: applied pharmacology and use as adjunctive treatment in chronic pain.” Postgraduate medical journal 80.949 (2004): 654-659.

Center For Substance Abuse Research. Methadone. University of Maryland (2016). Accessed on 8 November 2018 from Active ingredient: Methadone (2017). Accessed on 8 November 2018 from

Green, Mark, Scott Kellogg, and Mary Jeanne Kreek. “Methadone: History, pharmacology, neurobiology, and use.” Encyclopedia of Neuroscience. 3rd ed. Elsevier (2004).

The Pharmaceutical Journal. “Stopping Methadone During Pregnancy.” A Royal Pharmaceutical Society Publication. Accessed on 9 October 2018 from

The terms offer and acceptance. (2016, May 17). Retrieved from

[Accessed: November 26, 2021]

"The terms offer and acceptance.", 17 May 2016.

[Accessed: November 26, 2021] (2016) The terms offer and acceptance [Online].
Available at:

[Accessed: November 26, 2021]

"The terms offer and acceptance.", 17 May 2016

[Accessed: November 26, 2021]

"The terms offer and acceptance.", 17 May 2016

[Accessed: November 26, 2021]

"The terms offer and acceptance.", 17 May 2016

[Accessed: November 26, 2021]

"The terms offer and acceptance.", 17 May 2016

[Accessed: November 26, 2021]
Haven't found the right essay?
Get an expert to write you the one you need!

Professional writers and researchers


Sources and citation are provided


3 hour delivery