• Addiction & recovery

How Does Methadone Work?

Nzinga Harrison

May 7, 2021


Methadone is a long-acting prescription drug approved by the U.S. Food and Drug Administration (FDA) to help treat moderate to severe pain. It is also used to treat opioid use disorders, such as heroin addiction. The use of methadone in opioid addiction treatment is known by terms such as methadone maintenance treatment (MMT), opioid substitute therapy, medication-assisted treatment (MAT), and Medication for Opioid Use Disorder (MOUD). According to the Substance Abuse and Mental Health Services Administration (SAMHSA), methadone accounted for 21-25 percent of all individuals receiving treatment for opioid use disorder.

Methadone belongs to the opioid narcotic analgesics class of drugs and is a controlled substance that has a high risk for misuse and dependence. As such, most states require individuals to visit clinics to get their prescribed daily doses of methadone.

Methadone is available as:

  • Oral tablets
  • Oral dispersible tablets
  • Oral concentrate solution
  • Oral solution
  • Intravenous form 

How Does Methadone Work?

Methadone works by changing how the brain and the nervous system react to pain to treat a variety of chronic pain. When used as part of opioid addiction treatment, it works by interacting with opioid receptors in the brain to reduce symptoms of opioid withdrawal. The interaction also blocks the euphoric high caused by other opioids such as heroin, codeine, and morphine to prevent relapses during recovery.

The effects of methadone are slower than that of the other opioids. It also doesn’t cause euphoric highs in opioid-dependent individuals when used as prescribed and as part of a treatment program. However, methadone gradually builds up and stays in the body for as long as 1-3 days. 


Side Effects of Methadone 

Methadone can cause side effects that can range from mild to severe. The milder, more common side effects of methadone tend to disappear within a few days or a couple of weeks and include symptoms such as:

  • Constipation 
  • Nausea
  • Sleepiness 
  • Vomiting 
  • Tiredness 
  • Headache
  • Dizziness 
  • Stomach pain 
  • Slow breathing 
  • Itchy skin 
  • Profuse sweating 
  • Sexual problems 

The more severe side effects of methadone can be life-threatening. Some of such side effects are:

  • Shortness of breath 
  • Chest pain 
  • Lightheadedness 
  • Slowed or shallow breathing
  • Faintish 
  • Dizziness 
  • Confusion 
  • Low blood pressure
  • Pounding heart rate
  • Hallucinations 
  • Hives or rashes 
  • Swelling of the face, lips, tongue, or throat
  • Overdose death

Some of the severe side effects of methadone can indicate a medical emergency. Individuals are advised to stop taking the medication and contact a healthcare professional immediately if they experience severe side effects. 

Dangers of Methadone 

While methadone, if used as prescribed doses, does not generate any euphoric highs as other opioids, it does generate a few sedative effects that can be euphoric when taken in large doses or as an IV. The euphoric effects of methadone are limited. However, they are still strong enough that the National Highway Traffic Safety Administration (NHTSA) has deemed methadone users “not fit to drive” due to its side effects. 

The misuse of methadone for its sedative effects can lead to an increased risk of addiction and dependence. The potential risk remains the same for all individuals who use this medication. This is because methadone can cause tolerance when used for a prolonged period and cause people to take more of the drug to attain the same effect. As such, anyone allowed to take methadone at home rather than in a clinical setting should be vigilant of this risk. 

The use of alcohol or benzodiazepines while on methadone can be fatal. As methadone is a central nervous system depressant, combining it with other central nervous system depressants such as alcohol or Valium can lead to fatal consequences. The combination can cause dangerously low blood pressure, respiratory failure, coma, or even death. 

Methadone can interact with many different medications. Although some interactions do not pose any danger, some can cause adverse side effects. Drugs such as Pentazocine, nalbuphine, butorphanol, and buprenorphine should not be taken while on methadone as they tend to reduce methadone’s pain-relieving properties and cause withdrawals. 


Methadone Withdrawal 

Methadone withdrawal can be caused during abrupt cessation or dose reduction after a long period of use. Methadone withdrawal can appear 24-36 hours after the last use and include symptoms such as:

  • Tiredness
  • Anxiety 
  • Restlessness 
  • Sweating 
  • Watery eyes
  • Runny nose 
  • Yawning 
  • Sleeping troubles 

The initial symptoms of methadone withdrawal can be similar to the flu. However, unlike the flu, the symptoms of methadone withdrawal tend to remain quite severe for several days. Some symptoms can also peak after three days. Such symptoms of methadone withdrawal are: 

  • Muscle aches and pains 
  • Goosebumps 
  • Severe nausea
  • Vomiting 
  • Cramps 
  • Diarrhea
  • Depression 
  • Drug cravings 

Methadone withdrawal can be a difficult and dangerous process. The risk of experiencing a relapse during this phase is extremely high. And as such, it is vital to seek support and guidance from a healthcare provider or addiction specialists before going off this drug. Most doctors recommend remaining on low doses of methadone to mitigate withdrawal. Once they adjust to the low doses, they can slowly be tapered off the drug completely. 

How Does Methadone Work?

Methadone Overdose

Since methadone is a powerful opioid, it can cause an overdose when taken in high doses. People who consume too much methadone without a prescription or against medical advice are at a high risk of a methadone overdose. 

Methadone overdose is a medical emergency. Not recognizing the signs or receiving medical attention can result in fatal consequences. Some of the symptoms of a methadone overdose are:

  • Constricted pupils 
  • Dizziness 
  • Hypertension 
  • Loss of consciousness 
  • Nausea and vomiting 
  • Discoloration of the nails and fingertips 
  • Loss of muscle tone 
  • Cold, clammy skin 
  • Slow pulse
  • Slowed breathing
  • Respiratory depression 
  • Coma 

Make sure to contact your doctor or poison control if you think you have consumed too much methadone. Suppose the symptoms progress, head over to the nearest emergency department without delay. 

Evzio (naloxone) injection or Narcan (naloxone) nasal spray can be used to reverse methadone overdose. However, make sure to call emergency services right after administering this medication. Talk to your doctor about having prescription naloxone readily available in cases of an emergency. 


Alternatives to Methadone Treatment

While methadone has been successfully used to treat opioid addictions in the U.S. since the 1970s, other alternatives are equally as effective in the battle against substance use disorder. Some of such FDA approved medications that are utilized in MAT programs are:

  • BuprenorphineBuprenorphine has many advantages for individuals with opioid addiction and for those looking for an alternative to methadone treatment. Buprenorphine has a ceiling effect as a partial opioid agonist, which reduces respiratory depression and its risk of an accidental overdose. In terms of medication retention and decreased opioid use, buprenorphine-assisted treatment is just as effective as methadone.
  • Naltrexone – Intramuscular extended-release Naltrexone is a medication utilized in MAT for the treatment of OUD and AUD. Naltrexone isn’t an opioid, nor is it addictive, and nor does it cause any withdrawal effects during cessation. Naltrexone blocks the euphoric and sedative effects of opioids such as heroin, morphine, and codeine. And as a result, reduces or prevents opioid cravings with a minimum risk of misuse.
  • Vivitrol – Vivitrol is a non-addictive opioid antagonist that suppresses the brain’s response to opioids by reducing cravings. Vivitrol treatment is only utilized after the successful completion of a detox program.
  • Suboxone – Suboxone is the newest methadone substitute that incorporates buprenorphine (a partial opioid agonist) with naloxone (an opioid antagonist). Suboxone, like methadone, reduces addiction and cravings. And since buprenorphine reaches a ceiling effect at higher doses, it’s less likely to cause any fatal overdose.
  • Campral – Also known by its brand name Acamprosate, it’s designed to help decrease cravings during alcohol addiction treatment. Campral helps restore the chemical balance in the brain during treatment. Individuals experiencing anxiety, insomnia, or restlessness during alcohol cessation can greatly benefit from this medication.  
  • Chantix – Chantix, also known as Varenicline, is a prescription medicine used as an aid for smoking cessation. Chantix may be used alone or as a combination with other medications. New studies have suggested its efficacy in treating alcohol use disorder and opioid use disorder.

The right medication can help you maintain a positive state of mind and get you through the difficult periods of your recovery with greater success. And the MAT program at Eleanor Health is designed to meet the highest clinical safety and care levels. 

If you are seeking help with your loved one’s addiction, contact us today or complete our quick contact form below, to speak with an addiction treatment specialist.

If you need help with your substance use disorder, we are here to help you build your confidence and momentum towards the future you want. We provide treatment services for adults with alcohol, opioid, and other substance use disorders. We are currently located in LouisianaMassachusettsNew JerseyNorth CarolinaOhio, Texas, and Washington.

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