Addiction Treatment

Methadone Side Effects, Usage, Detox & Withdrawal Symptoms

Methadone was first synthesized in the 1930s and was later introduced during World War II as a painkiller. Methadone began to be used as a treatment for heroin addiction in the 1960s, particularly gaining prominence after the opening of the first methadone maintenance clinic in 1964. Since then, Methadone has been used to help people overcome their opiate dependence in both short-term and long-term programs.

However, much like any controlled drug, there are risks associated with taking Methadone in the form of mild to severe side effects, as well as the potential for misuse and abuse. It is important to have a thorough understanding of these risks before beginning treatment and to know how to identify common withdrawal signs and symptoms.

What Is Methadone?

Methadone[1] is classified as a synthetic opioid – which means it is a man-made substance that acts in a similar way to natural opiates like morphine and heroin, but it does not exactly mirror their chemical structure. The drug was designed as an effective alternative for individuals struggling to manage their opioid dependence.

Similar to the way heroin affects the pain receptors in the brain, Methadone is designed to help an individual relieve the pain associated with addiction withdrawal as well as reduce cravings. Methadone can be administered in the form of a tablet or liquid, and its effects can last up to 24 hours.

What Does Methadone Look Like?

While the appearance of Methadone can vary slightly depending on the manufacturer or the strength of the drug, there are typically two different ways it is administered – as an oral liquid solution or in a pill form.

As a liquid, Methadone is administered orally and usually comes in a red, cherry-flavored liquid or can also be clear and unflavored. In its pill format, Methadone will look like a white and round tablet with a score line in the middle to make it easier to break apart in smaller doses.
Methadone Side Effects

Methadone, a synthetic opioid, is categorized as a Schedule II drug under the Controlled Substance Act, and it’s only lawful to be administered by qualified medical personnel. This is because individuals using Methadone are at risk of experiencing a wide range of adverse effects, some of which may be severe and frequent.

Among some of the effects associated with methadone use, there are adverse effects[2] that can affect the heart and overall health of the body. These effects, in addition to the typical side effects that methadone users may encounter, include:

  • Nausea or Vomiting
  • Mood Changes
  • Chest Pain
  • Change in Heart Rate
  • Dry Mouth
  • Drowsiness
  • Sexual Dysfunction
  • Dizziness or Lightheadedness
  • Vision Problems
  • Sleep Changes
  • Weight Gain
  • Rash or Itchy Skin
  • Changes In Appetite
  • Stomach Pains
  • Constipation
  • Heavy Perspiration

Withdrawal Symptoms From Methadone

Since Methadone, by design, is intended to be a more suitable replacement for heroin or other opioids, it does contain addictive properties that can lead to certain withdrawal symptoms when weaning off of the drug.

While the withdrawal symptoms of Methadone may not be as severe or as long-lasting as those suffering from other opioid addictions, primarily due to its controlled administration, there are certain withdrawal symptoms that can occur, including:

  • Muscle Aches and Pains
  • Sweating
  • Nausea
  • Anxiety
  • Agitation
  • Dilated Pupils
  • Increased Heart Rate and Blood Pressure
  • Hallucinations
  • Seizures

Methadone Overdose Symptoms

Accidental or intentional misuse of Methadone can be potentially fatal, and it’s vital to watch for any signs of an overdose. Symptoms of a methadone overdose[3] include:

  • Difficulty Breathing
  • Physical Weakness or Dizziness
  • Cold, Clammy Skin
  • Slow or Irregular Heartbeat
  • Low Blood Pressure (Hypotension)
  • Seizures
  • Loss of Consciousness
  • Blue or Purple Lips and Fingernails

It’s absolutely vital if you or someone else experiences any of these symptoms while taking Methadone seek help. Get emergency medical treatment right away and call 911 immediately.

Methadone Side Effects, Usage, Detox & Withdrawal Symptoms

Long-Term Effects Of Methadone

Long-term use of Methadone can have certain physical effects on the body that, if left unchecked, can lead to potentially dangerous health complications. Some of the most common physical side effects associated with long-term methadone use include:

  • Physical Dependence – As the body continues to adapt to regular methadone consumption, it may begin to require it in order to function normally.
  • Increased Tolerance – Over time, the body may become too tolerant of Methadone, requiring higher doses of the medication in order to experience the same effects.
  • Cognitive Effects – Long-term Methadone use can lead to cognitive regression, including impaired attention, memory, or decision-making abilities.
  • Respiratory Depression – If taken for too long, Methadone can lead to slower and shallower breathing which can be dangerous at high doses.

Long-Term Side Effects Of Methadone

While many of the side effects associated with Methadone use are typically short-term, there are some potential long-term side effects. These may include tolerance and physical dependence, confusion, depression, increased risk of overdose, and an increased risk of developing other mental health issues.

Additionally, Methadone can interact with certain medications or supplements and may cause a dangerous reaction when combined. It is important to always speak with a qualified doctor or pharmacist about any potential drug interactions prior to taking Methadone.

Liquid Methadone Side Effects

Liquid Methadone is designed to be taken orally and, therefore, has many of the same side effects as other formulations of Methadone. These may include nausea, drowsiness, dizziness, dry mouth, weight gain, and rash or itchy skin. Like other formulations of methadone, liquid Methadone may cause digestive problems such as constipation, upset stomach, or abdominal pain.

Recover With Hope And Pursue Healing At Recovery Unplugged

Methadone has many benefits for individuals suffering from physical pain and opioid addiction. However, it is important to remember that the side effects can contribute to other addictive behaviors if not managed properly.

At Recovery Unplugged, we offer a comprehensive approach to recovery and drug addiction treatment that helps our clients break the dangerous cycle of methadone dependence. If you or someone you know needs help finding long-term sobriety and healing, reach out to us today and let us help.

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[1] SAMHSA. (n.d.). Methadone. Substance Abuse and Mental Health Services Administration (SAMHSA). Retrieved April 1, 2023, from

[2] Durrani, M., & Bansal, K. (2022, August 1). Methadone. U.S. National Library of Medicine. Retrieved April 1, 2023, from

[3] Anderson, I. B., & Kearney, T. E. (2000, January). Use of Methadone. The Western Journal of Medicine. Retrieved April 1, 2023, from