Methadone Side Effects, Uses, Purposes, Health Risks & Drug Addiction Treatment Options

We Level Up FL Treatment Center believes in making our clients substance-free as soon as possible so they can return to their everyday lives. Although most methadone detox plans include a long-drawn-out taper, We Level Up Detox Facilities aims to speed up this process and give the individual a fair chance at a life in recovery.

By We Level Up FL Treatment Center | Editor Yamilla Francese | Clinically Reviewed By Lauren Barry, LMFT, MCAP, QS, Director of Quality Assurance | Editorial Policy | Research Policy | Last Updated: March 29, 2023

What are the side effects of methadone?

Methadone side effects may be habit-forming. Take methadone exactly as directed. Do not take a larger dose; take it more often, or take it for a longer period or in a different way than your doctor prescribes. While taking methadone, discuss with your healthcare provider your pain treatment goals, length of methadone treatment, and other ways to manage your pain.

Tell your doctor if you or anyone in your family drinks or has drunk large amounts of alcohol ever, uses or has ever used street drugs, has overused prescription medications, or has had a drug overdose, or if you have or have ever had depression or another mental illness. There is a greater risk that you will overuse methadone if you have had any of these conditions. Talk to your healthcare provider immediately and ask for guidance if you think that you have an opioid addiction or experiencing the methadone side effects listed in this article.

What is Methadone?

Methadone is a long-acting synthetic opioid painkiller often used to relieve severe pain for someone expected to need pain medication for a long time and cannot be treated with other medicines [1]. This drug is also used to prevent opioid withdrawal symptoms in individuals addicted to opiate drugs and who are enrolled in addiction treatment programs to stop using or continue not using the drugs. 

Methadone is in a class of medications called opiate (narcotic) analgesics. It works to treat pain by changing the way the brain and nervous system respond to pain. Methadone works to treat people addicted to opiate drugs by producing similar effects and preventing withdrawal symptoms in people who have stopped using these drugs. When taken as prescribed, this opioid painkiller can be very useful in treating heroin addiction, but it, too, can be addictive, as it is still an opiate [2].

How is Methadone Used?

Methadone changes how the nervous system and the brain respond to pain. It reduces the painful symptoms of opiate withdrawal. It blocks the euphoric effects of opiate drugs such as morphine, heroin, and codeine, as well as semi-synthetic opioids like hydrocodone and oxycodone.The opioid-dependent patient takes a daily dose of methadone as a liquid or pill. Pain relief from a dose of methadone lasts about four to eight hours.

According to the Substance Abuse and Mental Health Service Administration (SAMHSA) [3], methadone is effective in higher doses, especially for heroin users, helping them stay in treatment programs longer.As with medications used in medication-assisted treatment (MAT), methadone is usually prescribed as part of a comprehensive treatment plan for opioid and opiate addiction that includes counseling and participation in social support programs.

People with methadone prescriptions must take this medication exactly as prescribed and do not adjust their dose without a doctor’s advice and oversight. It is easy to overdose on methadone due to the strength of one dose. Methadone and Suboxone are both opioids. While methadone treats chronic pain and opioid addiction, Suboxone is only approved to treat opioid dependence.

Methadone Side Effects

Overdose is one of the methadone side effects that require immediate medical treatment.
Overdose is one of the methadone side effects that require immediate medical treatment.

With short-term use, you may experience methadone side effects like:

  • Restlessness
  • Vomiting or Upset stomach
  • Slow breathing
  • Itchy skin
  • Heavy sweating
  • Constipation
  • Weight gain
  • Dry mouth
  • Sleep changes
  • Appetite changes
  • Headache
  • Stomach pain
  • Flushing
  • Vision problems
  • Mood changes
The major side effects of methadone are respiratory depression and, to a lesser degree, systemic hypotension. Contact us to get help.
The major side effects of methadone are respiratory depression and, to a lesser degree, systemic hypotension. Contact us to get help.

Learn More:

Methadone Mechanism of Action Drug Facts

Methadone Generic Name: Methadone (oral/injection) [ METH-a-done ]
Methadone Brand Names: Dolophine, Methadose, Methadose Sugar-Free, Diskets
Dosage Forms & Methadone Liquid Forms: Injectable solution; intravenous solution; oral concentrate; oral solution; oral tablet; oral tablet, dispersible.
Methadone Drug Class: Opioids (narcotic analgesics)
Methadone Schedule: Schedule II drug under the Controlled Substances Act.

Methadone Interactions

This medication can cause CNS depression and respiratory compromise; hence it should be used with extreme caution in patients with CNS-related pathologies such as trauma, increased intracranial pressure, dementia, delirium, etc. It should not be used in conjunction with medications or substances with similar depressant effects such as other opioids, benzodiazepines, alcohol, antipsychotics, etc., unless necessary. Drugs that may increase the clearance of methadone or decrease its effects must also be used with caution to prevent precipitating withdrawal symptoms.

The following examples are not an exhaustive list of drug interactions but provide some commonly documented drug interactions.

Examples of drugs that may increase methadone side effects long term and risk overdose symptoms: 

  • Ciprofloxacin
  • Benzodiazepines
  • Alcohol
  • Fluconazole
  • Cimetidine
  • Fluoxetine
  • Urine alkalizing agents

Examples of drugs that may decrease methadone effects and risk withdrawal symptoms:

  • Efavirenz
  • Phenobarbital
  • Phenytoin
  • Rifampin
  • Ritonavir
  • Carbamazepine
  • Urine acidifying agents

Methadone Clinic Rules and Regulations

It is crucial to seek accredited and professional options when searching for “methadone treatment near me” or “methadone doctors near me.” Opioid treatment programs (such as online methadone clinics, and clinic methadone treatment options) must meet federal certification and accreditation requirements and state licensing requirements.

Under federal regulations, opioid treatment programs must be certified by the federal Substance Abuse and Mental Health Services Administration (SAMHSA), which is part of the U.S. Department of Health and Human Services. The regulations also require these programs to be accredited by an independent, SAMHSA-approved accrediting body to dispense opioid treatment medications (e.g., the Commission on Accreditation of Rehabilitation Facilities (CARF) or the Joint Commission). Treatment programs must first obtain accreditation and then seek certification. Opioid treatment programs also must register with the federal Drug Enforcement Administration. [3]

To learn more visit:

Methadone Definition & Drug Fact Sheet by DEA. Publicly Made Available for Opioid Use Disorder Awareness

Methadone for Pain Management & Treatment of Opiate Dependence Statistics

According to the Substance Abuse and Mental Health Services Administration (SAMHSA), effective treatment for opioid use disorder includes medication-assisted treatment (MAT) which combines behavioral therapy and medications. The Food and Drug Administration (FDA) approved medications for use in treating opioid use disorder including methadone, buprenorphine (buprenorphine with naloxone), and naltrexone. Naltrexone is an opioid antagonist, methadone is an opioid agonist and buprenorphine is a partial opioid agonist. MAT has been found to reduce morbidity and mortality, decrease overdose deaths, reduce transmission of infectious disease, increase treatment retention, improve social functioning, and reduce criminal activity. [4]


More than 400,000 people in the United States received methadone as part of their addiction treatment in 2019.

Source: NIDA


Clients receiving treatment with methadone accounted for approximately 21 to 25 percent of all substance abuse treatment clients each year.

Source: NIDA


Deaths involving synthetic opioids other than methadone (primarily fentanyl) continued to rise with 56,516 overdose deaths reported in 2020.

Source: NIDA

Some methadone side effects are more serious. Call the doctor if you have the following:

  • Trouble breathing
  • Fainting or lightheadedness
  • Rash or hives
  • Swollen tongue, lips, throat, or face
  • Rapid heartbeat or chest pain
  • Confusion or hallucinations
  • A hoarse voice
  • Trouble swallowing
  • Seizures
  • Severe drowsiness
  • Unusual menstrual periods

Methadone Side Effects Requiring Immediate Medical Attention

Methadone overdose happens when a person intentionally or accidentally takes more than the recommended or average amount of this medicine. This can be on purpose or by accident. Make sure to let your doctors know about any medications you’re taking.

Even though the methadone side effects are different from those of other opioids, such as heroin, your body can still get used to it. This means you might need more methadone to feel the same effects. This is called tolerance, and it can happen with any other opioids. [4]

Your body can also become dependent on this drug and other opioids. Your brain relies on the pain relief they bring, and you have withdrawal symptoms if you stop taking them suddenly. Some people may take methadone with other opioid painkillers, such as oxycodone. High doses or combining methadone with other drugs or painkillers can raise someone’s risk of overdose. These painkillers include oxycontin, hydrocodone (Vicodin), and morphine.

Symptoms of Methadone Overdose

  • Vomiting
  • Convulsions
  • Slow, shallow breathing, known as respiratory depression
  • Clammy or bluish skin
  • Blue-tinted lips and fingertips
  • Extreme fatigue to the point of being unable to stay awake
  • Stupor
  • Coma
  • Death

Combining methadone with other illegal or prescription drugs can also lead to serious heart problems. These heart problems range from arrhythmia to heart attacks.

Methadone Withdrawal Timeline and Symptoms

Symptoms of methadone withdrawal, also sometimes referred to as methadone detox, typically begin to appear roughly 24-36 hours after you last used the drug. A physician supervises the detox process.  The duration of the process differs from person to person but may last anywhere from 2-3 weeks up to 6 months.

You may be having withdrawal if, within the first 30 hours that you stop taking methadone, you might struggle with the following:

  • Tiredness
  • Anxiety
  • Restlessness
  • Sweating
  • Watery Eyes
  • Runny Nose
  • Yawning
  • Trouble Sleeping

At first, symptoms of methadone withdrawal may seem like the flu.  But unlike with the flu, withdrawal symptoms can persist severely for several days.  Specific symptoms may peak after about three days. These include:

  • Muscle Aches and Pains
  • Goosebumps
  • Severe Nausea
  • Vomiting
  • Cramps
  • Diarrhea
  • Depression
  • Drug Cravings

The symptoms will likely be at their worst throughout the first week.  However, some symptoms can last even longer than a week.  These include low energy levels, anxiety, difficulty sleeping, and depression.

Withdrawal can cause much distress as part of methadone side effects, and the risk of returning to the use of other opiates can increase.  Therefore, some people discuss continuing on methadone treatment but at lower doses, if permitted.  Once a person becomes stable at a lower amount, another effort at tapering can be discussed with your doctor.

Methadone Withdrawal or Taper

Whether you’ve been on methadone for an extended period or a short period, a taper protocol is the choicest way to come off of methadone.   A taper means to lessen doses in a scheduled time.  The prescribing physician will develop a taper schedule based on what is most suitable for you, your current dose, and how long you’ve been on methadone. Following your provider’s taper schedule and instructions is essential to avoid any adverse symptoms from detoxing too suddenly.

Methadone side effects cause health risks and overdose can be fatal. Always seek professional help when experiencing drug overdose symptoms for a safe and secure treatment.
Methadone side effects cause health risks and overdose can be fatal. Always seek professional help when experiencing drug overdose symptoms for a safe and secure treatment.

Medical Methadone Detox

Medical detox in a treatment facility can aid in detoxing or tapering methadone. The physicians in the treatment facility will monitor your symptoms and vitals during the process.  They can also prescribe non-narcotic medication to relieve signs that may manifest due to the detox. As part of medical detox, clients are engaged in clinical treatment to start addressing their addiction’s underlying issues.

On-Going Care and Support

Because of the withdrawal process and the possible presence of PAWs (Post Acute Withdrawal Syndrome)  with methadone detox, someone must engage in continued care beyond the initial detox process. They should engage in residential treatment after detox to get proper support through this process. This clinical care can help when someone feels triggered or wants to use the drug again and provide the means and resources to explore the addiction and underlying issues.

Whether you’ve been on methadone for a long or short time, it is possible to come off it with the proper support and medical assistance.  Although the methadone side effects and post-acute withdrawal process can sound daunting, scary, or challenging, it can effectively and safely detox from methadone with the proper support.

Quitting Cold Turkey

Many people try to ride out methadone withdrawal on their own.  Though opioid withdrawal may not be life-threatening in most cases, it can be excruciating.  It can also lead to cravings and a return to drug use if left untreated.  One of the most significant risks of trying to stop using methadone cold turkey is relapse. [1]

In addition, other health complications may occur in connection with withdrawal sickness that may necessitate immediate medical attention, including:

  • Dehydration and electrolyte imbalance from vomiting and diarrhea.
  • Aspiration from breathing stomach contents into the lungs can cause lung infection.

The lack of medical care to manage withdrawal effects and methadone side effects and the strong possibility of relapse due to the distress make cold turkey an unwise detox method. A schedule for decreasing methadone dosing will be best determined and potentially regulated by your treating physician.

Notwithstanding how someone becomes dependent on methadone side effects, the most secure way to quit is to slowly lessen the dose over time—a process known as tapering.  A taper can help prevent severe withdrawal symptoms and decrease the risk of potential withdrawal-associated medical problems. Weaning or tapering should only occur under the supervision of a medical professional, who can assess withdrawal progress and best help the individual regulate doses.

  1. What are the methadone side effects long term?

    If you are wondering, “what are the side effects of methadone long term?”, “what are the side effects of long term methadone use?”, “what are the side effects of methadone liquid?”, “what are the long-term side effects of methadone?”, or “what are the long term side effects of methadone?”, the answer is for many people, methadone addiction is a very real problem. Some doctors are reluctant to administer methadone to their patients at all since the pain relief it offers in circumstances where it is prescribed for pain can result in chemical dependency in a person with chronic pain. Those who do prescribe methadone frequently go above and beyond to keep an eye on their patients’ prescriptions and look out for any misuse that might portend the onset of a habit.

  2. What are the liquid methadone side effects?

    Possible side effects include sweating, lightheadedness, dizziness, dry mouth, nausea, vomiting, and constipation. After using this drug for a while, some of these adverse effects can go away. Inform your doctor or pharmacist as soon as possible if any of these side effects persist or get worse.

  3. What are methadone side effects on body?

    If you are wondering, “what are the methadone skin side effects?”, the answer is having hives or a rash, as well as facial, lip, tongue, or throat swelling. ache in the chest. Feel your heart racing or thumping. experience confusion or hallucinations.

  4. What are the methadone side effects on brain?

    A growing body of research indicates that long-term use of heroin may have detrimental consequences on the brain’s structure, metabolism, function, and cognitive state because methadone, a synthetic opioid, can cause neuronal alterations in users’ brains in addition to its therapeutic impact.

  5. What are the methadone side effects on heart?

    Methadone’s primary cardiac side effects are torsade de pointes and QT interval prolongation. Changes in QT dispersion, pathological U waves, Taku-Tsubo syndrome (stress cardiomyopathy), Brugada-like syndrome, and coronary artery disorders are among the further complications.

  6. What are the methadone side effects on stomach?

    Adrenal gland issues could result from this medication. If you have diarrhea, dizziness, fainting, lack of appetite, mental depression, nausea, skin rash, unusual tiredness or weakness, or vomiting, consult your doctor immediately once.

  7. What are the methadone side effects on teeth?

    If you are wondering, “what are the methadone side effects teeth?”, the answer is acidic drugs like methadone can damage tooth enamel. Methadone causes a decrease in saliva, which helps to protect your mouth and prevent tooth decay. The syrup that is used to make methadone mixture contains sugar. Sugar stimulates the production of acid by oral bacteria, which can cause tooth decay.

Methadone Detox Methods for Safe Methadone Withdrawal

Methadone, when prescribed for opiate addiction, is eventually tapered down after a lengthened time.  It is known in the opiate family for having the most prolonged detox, which also makes the typical taper a lengthy period, sometimes extending for over a year.

We Level Up FL Treatment Center believes in making our clients substance-free as soon as possible so they can return to their everyday lives. Although most methadone detox plans include a long-drawn-out taper, We Level Up Detox Facilities aims to speed up this process and give the individual a fair chance at a life in recovery.

If you or someone you know is struggling with methadone side effects or abuse, help is just a phone call away.  So call us now here at We Level Up FL. We are here to help you.

Alumni Coordinator, Nicole Baxter’s Methadone Addiction Recovery Journey With Support From Daughter Video

Nicole Baxter’s Addiction Recovery Story and Testimonial Video

“I’m here with the Nicole Baxter, one of our alumni coordinators.

What does your bottom look like?

My bottom was like a spiritual bottom. I was I wanted to die every day. I was putting a lot of drugs in my system every day, trying to make the pain go away. And it wasn’t going away anymore. So I was using for no reason anymore, because when I first started using, that’s what that was for, was to make it all go away. And it was still there. So it was like a spiritual bottom for me. I felt dead inside, and I was looking for a way out. So I prayed really hard that night, and my brother a few days later called me.

How long were you in treatment for?

A long time. I went to detox for almost a month because I was on methadone when I came down here, so my detox was painful when I finally came.

Knowing that I was away from them was hard to deal with because it was like a reality check. It was the hardest part of getting sober.

It was my biggest excuse prior to coming to not like that was my excuse. Like, I can’t go to treatment, I can’t be away my kids, but, like, I wasn’t a mom anyway, so I was getting high every day, you know? And I struggled with telling my daughter the truth about where I was. She thought that I had just comedown here to visit her uncle.

It wasn’t until I was in, like, IOP one afternoon, my therapist had me go outside and make a phone call, and I told her that I had come down for detox. And in my head, I thought that she was gonna hate me. But it was the best conversation ever. All she said to me was, Mummy, I just want you to get better. I’m just happy that you’re getting better.

What is your life like today? In sobriety, in recovery?

I’m happy, sober happier than I was high. And I thought that I’d never be happy sober. I didn’t think it was possible.

What do you do for your recovery every day? I have sponsees that I talk to on a daily basis, so I give back what I was given, which is what I think keeps me sober at most. I go to meetings, I work in treatment. So I’m like hands on with clients all daylong, people that are right where I was. So I try my best to use my story to help them get to a better place.

Oh, yeah.”

Does Addiction Rehab Work?

Longer stays in treatment frequently result in better outcomes, however success can vary from person to person. Detox alone is rarely beneficial for long-term recovery. Does treatment work? Attending treatment increases a person’s chances of long-term recovery compared to not attending.

Search We Level Up FL Methadone Side Effects Topics, & Resources

[1]  Opiate and Opioid Withdrawal – U.S. National Library of Medicine
[2] NCBI –
[3] SAMHSA –
[4] We Level Up Addiction Treatment Center – Heroin Detox

[5] Treating Opioid Use Disorder During Pregnancy and Risks of Opioid Misuse During Pregnancy – (NIDA) National Institute on Drug Abuse Available from:,opioid%20use%20disorder%20during%20pregnancy.&text=While%20NAS%20may%20still%20occur,in%20the%20absence%20of%20treatment.

[6] BUPRENORPHINE – DEA Diversion Control Division Available from:

[7] Moghadam MS, Alavinia M. The effects of gabapentin on methadone based addiction treatment: a randomized controlled trial. Pak J Pharm Sci. 2013 Sep;26(5):985-9. PMID: 24035957. Available from:

[8] McCance-Katz EF, Sullivan LE, Nallani S. Drug interactions of clinical importance among the opioids, methadone, and buprenorphine, and other frequently prescribed medications: a review. Am J Addict. 2010 Jan-Feb;19(1):4-16. DOI: 10.1111/j.1521-0391.2009.00005.x. PMID: 20132117; PMCID: PMC3334287. Available from:

[9] Laur DF, Sinkovich J, Betley K. A comparison of intraoperative morphine sulfate and methadone hydrochloride on postoperative visual analog scale pain scores and narcotic requirements. CRNA. 1995 Feb;6(1):21-5. PMID: 7599543. Available from:

[10] Clinical Guidelines for Withdrawal Management and Treatment of Drug Dependence in Closed Settings. Geneva: World Health Organization; 2009. 4, Withdrawal Management. Available from: