Understanding the Side Effects of Methadone

Nausea is one of the common side effects of methadone, as explained by Revive Treatment Centers

Methadone is a long-acting opioid, and therefore, it needs to be taken exactly as directed. Proper dosing and medical supervision are crucial to ensure it works safely and effectively. Understanding the side effects of methadone and how it interacts with the body can help patients and caregivers make informed decisions and avoid potential complications.

Explore common and more serious adverse effects of methadone with Revive Treatment Centers, experts in using methadone to treat addiction, and discover valuable tips to help ease the side effects.

What Is Methadone and What Is It Used For?

Methadone is a powerful medication primarily used for two purposes: managing severe pain and supporting recovery from opioid addiction. It has been in use since the mid-1960s and is often a key part of treatment programs for individuals trying to stop using drugs like heroin or prescription opioids.

One of the reasons methadone is so important is that it helps ease withdrawal symptoms and cravings, making it easier for people to stay clean and avoid relapse. Methadone works without creating the same kind of high as other opioids when taken as prescribed, which helps people focus on their recovery.

Common Side Effects of Methadone

While methadone can be a really helpful medication, especially for managing pain or helping with opioid addiction, it does come with a number of side effects. A lot of people who take methadone experience symptoms such as nausea, constipation, dizziness, and drowsiness. These aren’t usually dangerous, but they can definitely be annoying and affect your day-to-day life. The good news is, most of them can be managed once you know what to expect and how to deal with them.

Nausea and Vomiting

Feeling nauseous or even throwing up is one of the more common methadone side effects on the stomach, especially in the first few days after starting treatment or when your dose changes. Why will methadone make you sick? It happens because methadone can irritate the stomach or affect the part of the brain that controls nausea.

What can help?

  • Try taking methadone with food.
  • Stick to bland, easy-to-digest meals.
  • Ginger tea or mints can sometimes help settle your stomach.
  • If it’s really bad, talk to your doctor; there are medications that can help with nausea.

Constipation

Does methadone make you constipated? 

Yes. Constipation is a very common issue for people on methadone; in fact, it happens to most long-term users. That’s because methadone slows down how your digestive system moves, which makes it harder for your body to process and pass food.

What can help?

  • Drink more water throughout the day.
  • Eat more fiber (fruits, veggies, whole grains).
  • Stay active: moving your body helps keep your digestive system working properly. Even light activity, like a short walk after meals, can stimulate your intestines and make it easier to have regular bowel movements.
  • Take a gentle laxative or stool softener regularly (ask your doctor first).
Two men eating watermelon slices outdoors at a table.

Drowsiness and Fatigue

Does methadone make you tired?

Feeling tired or a bit out of it is another side effect of methadone, especially when you’re getting used to it or if your dose is a little high. It can hit harder if you take it at certain times of day or if you’re already low on sleep.

What can help?

  • Try to take your dose at a time when being a little drowsy won’t cause problems (like not right before work or driving).
  • Avoid alcohol or other medications that also make you sleepy.
  • If you’re constantly exhausted, it might mean your dose needs adjusting; talk to your provider.

Sweating

The connection between methadone and sweating is documented by many people. Excessive sweating, especially during the day or while sleeping, is something a lot of people on methadone experience. It’s not dangerous, but it can definitely be uncomfortable and sometimes even embarrassing.

What can help?

  • Wearing breathable, loose-fitting clothes.
  • Using clinical-strength antiperspirants.
  • Showering more frequently if needed.
  • If it’s severe or bothersome, mention it to your doctor; there may be other options.

Less Common but Serious Side Effects of Methadone

Most people who take methadone don’t run into major complications, but as with any strong medication, there are some less common side effects that can be serious, even life-threatening, if not caught early. This includes trouble breathing, heart rhythm issues, and withdrawal symptoms if the medication isn’t taken properly. It’s important to know what to look out for so you can act quickly if something doesn’t feel right.

Respiratory Depression

One of the most serious risks with methadone is something called respiratory depression. That’s when your breathing slows down too much, sometimes to a dangerous level. This can happen if your dose is too high, if you mix methadone with other sedating drugs (such as alcohol, benzodiazepines, or sleeping pills), or if your body isn’t used to opioids.

Signs to watch for:

  • Slow, shallow breathing
  • Feeling extremely drowsy or hard to wake up
  • Blue lips or fingertips
  • Confusion or dizziness

If you notice any of these in yourself or someone else, it is crucial to get medical help right away; it can be life-saving.

Cardiac Arrhythmias

Occasionally, there is a link between methadone and heart problems. Methadone can sometimes affect how your heart beats. In rare cases, it can cause a problem called QT interval prolongation, which essentially means the heart takes longer than normal to reset between beats. This can lead to an irregular heartbeat, which can be dangerous if not caught early.

Because of this, doctors might do a heart test called an EKG (or ECG) before you start methadone, and sometimes during treatment too. This helps them make sure your heart is beating safely.

Important Considerations about Methadone and Heart Problems

It is crucial to be aware of the following factors that may impact the occurrence of cardiac arrhythmias:

  • If you already have heart problems, this risk may be higher.
  • Other medications you’re taking can also affect your heart rhythm, so it’s important to share your full medication list with your doctor.
  • If you feel faint, dizzy, or have a racing heartbeat, it’s worth checking out; don’t ignore it.

Dependency and Withdrawal

Even though methadone is used to treat addiction, it’s still an opioid, which means your body can become dependent on it.  This doesn’t mean you’re doing something wrong; it just means your system adjusts to having it. If you stop taking it suddenly, you might go through withdrawal symptoms like anxiety, sweating, nausea, chills, or muscle aches. 

The key is to taper off slowly, under medical supervision, if and when it’s time to stop. Trying to quit cold turkey is not only uncomfortable, it can be risky.

Additionally, due to the frequency of use, a long-term effect of methadone is the increased risk of overdose.

Managing Side Effects While on Methadone

Dealing with the side effects of methadone isn’t easy, but there are many strategies that can help you feel more comfortable while you’re on methadone. The key is to listen to your body, keep track of any changes, and stay in regular contact with your healthcare provider.

Firstly, make sure you keep up with your regular check-ups. Even if you’re feeling fine, these visits let your doctor monitor how the medication is affecting your heart, breathing, and overall health. The doctor might adjust your dose or suggest ways to deal with side effects like constipation, drowsiness, or sweating.

Female doctor checking patient's pulse during consultation.

It also helps to make a few simple lifestyle changes. Staying hydrated, eating fiber-rich foods like fruits, vegetables, whole grains, and beans, getting a bit of exercise, and keeping up with your dental care can all make a difference. If you’re feeling tired or foggy, try to plan your day around when the medication hits you hardest.

When to Seek Medical Attention

It’s essential to know when to check in with your doctor while you’re on methadone. If side effects are mild, they might just be annoying, but if they start getting worse or interfere with your daily life, don’t just tough it out, rather reach out. Most importantly, speak up if something doesn’t feel right. Don’t assume it’s just part of it. Your doctor can’t help unless they know what you’re going through, and chances are, there’s a way to make things more manageable.

You should definitely contact your healthcare provider if you notice any of the following symptoms:

  • Trouble breathing or feeling very short of breath
  • Extreme drowsiness or hard-to-wake-up feelings
  • Fast, irregular, or pounding heartbeat
  • Severe dizziness or fainting
  • Intense nausea, vomiting, or stomach pain
  • Signs of allergic reactions, like rash, swelling, or difficulty swallowing

Even if you’re not sure whether a symptom is serious, it’s better to ask. Your doctor can help figure out what’s going on and make sure you stay safe. Remember, good communication with your healthcare team is key to getting the best care while on methadone.

Making Methadone Work for You

Methadone can be a great tool for managing pain and helping with recovery from opioid addiction. But like any strong medicine, it comes with side effects, some more noticeable than others. That’s why it’s so important to know what to expect and keep an eye on how you’re feeling while taking it.

If something doesn’t feel right, don’t ignore it. Talk to your doctor or healthcare team; they’re there to help you stay safe and make sure the treatment is working for you. Everyone reacts a little differently, so keeping that line of communication open makes a big difference.

In short: stay informed about methadone side effects, stay in touch with your provider, and listen to your body. That’s the best way to get the most out of methadone while keeping yourself safe and supported.

If you or a loved one is struggling with opioid addiction and want to know how methadone can help, Revive Treatment Centers is here to help. As an outpatient clinic specializing in Medically-Assisted Treatment (MAT) with methadone, Revive provides compassionate, expert care tailored to your recovery journey. Contact Revive Treatment Centers today to learn more about how we can support you every step of the way.

FAQs About Methadone Side Effects

Can methadone lead to addiction?

It’s a good question, and the answer is a bit of a yes and no. Methadone is used to help people overcome addiction, especially to opioids, by easing withdrawal symptoms and cutting cravings. But because it’s a strong medication, it can also cause dependency if it’s not taken exactly as prescribed. That’s why it’s super important to use methadone under close medical supervision. Your doctor will help make sure you’re using the right dose and guide you through the methadone treatment process safely, so you get the benefits without getting stuck on the medication itself.

Does methadone make you itch?

Yes, it can! Itching is a common side effect of methadone and other opioids. It doesn’t mean you’re allergic; it’s usually just how the body reacts to the medication. The itching might be mild or more noticeable, and for some people, it goes away over time. If it’s bothering you a lot, let your doctor know. They might adjust your dose or suggest something to help.

What are the side effects of taking methadone during pregnancy?

Methadone is often used during pregnancy as part of a treatment plan for opioid addiction, and when managed carefully by a doctor, it can be much safer than continuing to use street drugs or going through withdrawal. That said, babies born to moms on methadone might experience something called neonatal abstinence syndrome (NAS), which means they can have withdrawal symptoms after birth. These symptoms can usually be treated, and doctors will keep a close eye on the baby. It’s super important to work closely with your healthcare team to make sure both you and your baby stay healthy even if you do experience methadone pregnancy side effects.

Does methadone cause weight gain?

It can, but not for everyone. Some people on methadone notice they gain weight over time, and it could be due to changes in appetite, metabolism, or lifestyle. Sometimes it’s just part of feeling more stable and eating more regularly. If weight gain becomes a concern, you can talk to your doctor or a nutritionist about ways to stay balanced.

Can methadone have an impact on dental health?

Yes, it can. Methadone dental side effects include a dry mouth, which might not sound like a big deal, but it actually makes it easier for cavities and gum problems to develop. Some people also crave sugary snacks more often while on methadone, which doesn’t help teeth either. Brushing, flossing, drinking plenty of water, and seeing a dentist regularly can go a long way in keeping your mouth healthy while on methadone.