What are the Side Effects of Methadone

Medically Reviewed by: Charley Allen

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Methadone is part of a class of drugs referred to as opioids.

Prescription drugs of this class are generally used for the treatment and management of pain. Originally methadone, which was invented by German doctors during World War II, was used for this purpose. However, the effects of methadone are unique. So what are the side effects of methadone?

Its effects come on more slowly and it blocks the effects of other opioids. Because methadone lasts much longer in the body than other opioids such as morphine or oxycodone, it is far easier to taper off of methadone. As such, today the drug is often prescribed as part of a treatment regimen for addiction to heroin and other opioids.

How is Methadone Taken?

The dosing of methadone, according to most medication guides, depends on the intensity of an addict’s addiction to whichever other opioid(s) they’re using. For pain management, patients are usually told to take methadone every 12 hours. But for addiction management, an initial dose of 20 to 30 mg is usually administered. The idea is to provide enough to prevent withdrawal symptoms but not enough for intoxication.

After a few hours, if the original dosage proves insufficient, another dose of 5 or 10 mg is often supplied. 40 mg is usually considered the maximum medically allowed dose per day. It is important for addicts to be under careful medical supervision when being treated for methadone to make sure proper dosages are applied.

While methadone can and often is used legitimately to treat opioid addiction, there is always the risk that a patient or recreational user can develop drug addiction to methadone itself. Like other opioids, methadone is physically and psychologically addictive. While it is normally prescribed in tablet, powder, or liquid form, addicts who are looking for quicker or more intense effects often inject it. This method exposes them to other risks, including HIV.

Physical and Psychological Side Effects of Methadone

Physical side effects of methadone vary depending on dosage and how long it is used. Short term side effects often include stomach issues such as nausea, vomiting, or constipation. Respiratory problems sometimes occur as well. Breathing tends to slow under the influence of methadone. Discomforts such heavy sweating and itchy skin are also known to happen. Some methadone users also experience sexual problems.

The psychological effects of methadone use vary between a feeling of restlessness and sedation. These mood swings are common while taking methadone. One moment a user can feel euphoria and at another they might experience extreme lethargy.

Long Term Side Effects of Methadone

Over the long term or at higher dosages, side effects can become more serious. Slowed breathing can intensify to dangerous levels. Users can experience a feeling of lightheadedness and even faint. Hives, rash, and swollen lips, tongue, throat, or face can occur if an allergy to methadone is present. Sometimes methadone users taking heavy doses experience chest pain or changes in heart rhythm. It is even possible to experience confusion bordering on psychosis, sometimes leading to hallucinations.

Allergies and Drug Interactions

Some people can also experience an allergic reaction to methadone. Common symptoms of an allergy to methadone include hives and difficulty breathing. If you experience any of these symptoms, seek medical attention immediately.

Methadone also poses unique risks when combined with other substances. It is common for drug interactions to change or amplify the effects of substances. In the case of methadone combined with muscle relaxants, the combination can be life threatening.

Both substances slow down the central nervous system and can result in difficulty breathing, coma, or even death. Combining methadone with antipsychotics, tricyclic antidepressants, and certain heart medications can also increase the risk of an irregular heart rhythm. If any of these more serious side effects occur, it is important to talk to your doctor and seek medical attention immediately.

Most importantly, methadone use carries a high rate of addiction and dependency — even if it is being used for the treatment of those same problems. As such, it should only be used under the careful supervision of a doctor or pharmacist and only at prescribed doses.

Using Methadone Safely as Part of a Treatment Program

Methadone can be a valuable part of a treatment program for opioid addiction. It can hamper some of the more adverse effects of other opioids as well as stymie cravings. Unfortunately, methadone is not without its own risks. Being aware of the side effects is a good first line of defense.

For addicts under careful medical supervision who are also receiving more holistic help at an out-patient or in-patient treatment center, methadone can be a powerful supplementary treatment for opioid addiction. After going through these treatment regimens, a recovering addict can hope to be sober for a very long time.

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Edited by: David Beasley

David Beasley - Design for Recovery

David Beasley is a certified RADT (Registered Alcohol/Drug Technician). David, moved to California from North Carolina after many failed attempts to get sober.

Medically Reviewed by: Charley Allen

Charley earned his Masters of Clinical Psychology from Antioch University, Los Angeles, and is a California Licensed Marriage and Family Therapist (LMFT).He teaches mindfulness to both adults and children in group setting such as schools, corporate workplaces, and medical treatment facilities.

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