Methadone (Oral)

Methadone is a round-the-clock pain relief medication. It is not suitable for the treatment of infrequent, mild pain.


In the US, methadone is known under several different brand names, including:

  • Dolophine
  • Diskets Dispersible
  • Methadose
  • Methadone HCI Intensol

It is a prescription only medication that comes in various oral preparations, including liquid, solution, tablets, and tablets for suspension.

Methadone is used for the treatment of severe to moderate pain when 24/7 pain relief is required for a long-term course. This drug is not suitable for treating infrequent, once in a while pain. Methadone should be used with caution and under your doctor's supervision, as it can become addictive. This medication is also used to deal with addition to heroin and other opioid drugs, together with counseling and other medical supervision.

Methadone is one of a group of narcotic analgesic medicines, which act on the central nervous system to provide pain relief.

Taking a course of methadone will not cure your illness or health condition, but it can be very effective in taking away the severe pain you are suffering.

Conditions treated

  • Severe to moderate pain as a long-term drug therapy

Type of medicine

  • Opioid analgesic
  • Oral: tablets, solution, liquid, tablets for suspension

Side effects

In addition to the pain relieving effects it is intended to provide, methadone can cause some side effects in certain patients. You may not experience any of these effects, but if you do, you may need to seek further medical attention.

You should check with your health care professional right away if you notice any of the following listed effects:

  • Weight gain
  • Unusual tiredness or weakness
  • Unusual bleeding or bruising
  • Trouble urinating
  • Trouble sleeping
  • Tenderness
  • Swelling or bloating of the arms, face, hands, feet, or lower legs
  • Sweating
  • Seizures
  • Swelling or puffiness of the eyelids, eyes, face, tongue, or lips
  • Red pinpoint skin spots
  • Blue or pale lips, fingernails, or skin
  • Pain
  • Tingling or numbness in the hands, lips, or feet
  • Nausea or vomiting
  • Muscle pains or cramp
  • Poor appetite
  • Irregular, rapid, slow, or shallow breathing
  • Irregular heartbeat
  • Increased thirst
  • Increased sweating
  • Itching, hives, or skin rashes
  • Headaches
  • Rapid, slow, or irregular heartbeat
  • Fainting
  • Extreme fatigue
  • Dryness of the mouth
  • Feeling dizzy, faint, or lightheaded when rising suddenly from a prone or seated position
  • Dizziness
  • Dilated neck veins
  • Difficulty in swallowing
  • Difficult, rapid, noisy breathing, sometimes with wheezing
  • Troubled breathing
  • Decreased urine output
  • Coughing that produces a pink frothy sputum
  • Coughing
  • Convulsions
  • Confusion
  • Chest discomfort or pains
  • Changes in skin coloration
  • Inability to see colors, especially yellow or blue
  • A bulging soft area on the head of a child
  • Blurred vision
  • Blood in the stools or urine
  • Bleeding gums
  • Black, tarry stools

You may experience some side effects that will resolve themselves without any need for you to see your doctor. These effects often go away when your body gets used to the drug. In addition, your health care professional may be able to suggest ways of preventing or reducing many of these effects.

If any of the following effects persist or are especially troublesome, ask your health care professional for advice:

  • Welts
  • Weight changes
  • Tunnel vision
  • Swelling, redness, soreness of the tongue
  • Seeing halos around lights
  • Restlessness
  • Over-bright appearance of lights
  • Night blindness
  • Loss or lack of strength
  • Irritability
  • Inability to have or keep an erection
  • Double vision
  • Disturbed color perception
  • Decreased libido
  • Constipation
  • Confusion about time, identity, and place
  • Blurring or loss of vision
  • Anxiety
  • Absent or irregular menstrual periods
  • A false or unusual sense of well-being

There may be other side effects experienced by patients taking methadone that are not included in this guide. If you notice any other odd effects, mention them to your doctor right away.


You must use methadone only as instructed by your health care professional. Do not use more or less of it, take it more often, or use it for a longer period than you have been told to. This is particularly important in the elderly, as old people tend to be more sensitive to the effects of analgesics.

You will be given a patient information leaflet when you get your prescription of methadone. Be sure to read the leaflet carefully and follow the instructions it contains. If you are unsure about anything regarding your use of methadone, check with your health care professional.

When using the tablet form of this medicine, you must swallow the tablets whole without breaking, chewing, dissolving, or crushing them.

Patients should be aware that the dose of methadone prescribed will vary across different patients. It is important that you stick to the dosage instructions you were given by your health care professional or those on the product label. The information contained here is purely based on the average for this drug. Do not change your dose if it is different, unless you are told to by your health care professional.

The size of your doses will depend on the strength of the preparation you are given. In addition, the number of daily doses you use, the time you leave between them, and the total duration of your course of treatment will depend on a number of factors, including your medical condition and how your body reacts to the drug.

Tablets for moderate or severe pain relief. For patients using Dolophine as a primary pain medication:

  • Adults: Initially, take 2.5 mg eight to 12 hourly. Your health care professional may change your dose as required. Do not exceed your prescribed in any 24 hour period.
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    • Children: The use and dose rate of this medicine will be determined by your child's GP.

Tablets for moderate or severe pain relief. For patients changing to Dolophine from other opioids:

  • Adults: The dose will be calculated by your health care professional based on your previous dose. Take your methadone every eight to 12 hours. Your health care professional may change your dose as required. Do not exceed your prescribed in any 24 hour period.
  • Children: The use and dose rate of this medicine will be determined by your child's GP.

For opioid addiction:

  • Adults: Initially, take 20 mg to 30 mg in one daily dose. Your health care professional may change your dose as required up to a maximum of 40 mg daily. Do not exceed your prescribed in any 24 hour period.
  • Children: The use and dose rate of this medicine will be determined by your child's GP.

If you forget to take a dose of your methadone, you should take it right away. However, if your next scheduled dose is nearly due, leave out the one you forgot and revert to your usual dosage schedule.

If you are using methadone to treat opioid addiction and forget to take a dose, just take your next prescribed dose the next day as scheduled.

Do not take a double dose.

Never share your methadone prescription with anyone else.


Drug interactions

There are some drugs that should never be used at the same time, as doing so could cause a dangerous interaction. However, in some cases it may be appropriate to use two different drugs together, even though an interaction may take place. In such cases, your health care professional may decide to alter your dose or advise you to take other precautions.

While you are using methadone, it is very important that you tell your doctor if you are using any other medicines, especially the drugs listed below.

It is not generally recommended to use methadone with any of the following drugs. Your health care professional may decide not to treat you with methadone or may change some of the other drugs you are taking:

  • Ziprasidone
  • Tranylcypromine
  • Toloxatone
  • Thioridazine
  • Terfenadine
  • Sparfloxacin
  • Selegiline
  • Rasagiline
  • Procarbazine
  • Posaconazole
  • Piperaquine
  • Pimozide
  • Phenelzine
  • Pargyline
  • Nialamide
  • Nelfinavir
  • Naltrexone
  • Moclobemide
  • Mesoridazine
  • Linezolid
  • Lazabemide
  • Ketoconazole
  • Itraconazole
  • Isocarboxazid
  • Iproniazid
  • Furazolidone
  • Fluconazole
  • Dronedarone
  • Clorgyline
  • Cisapride
  • Brofaromine
  • Bepridil
  • Amisulpride
  • Amifampridine
  • Zuclopenthixol
  • Zotepine
  • Zopiclone
  • Zolpidem
  • Zaleplon
  • Vortioxetine
  • Vinflunine
  • Vilazodone
  • Vemurafenib
  • Vardenafil
  • Vandetanib
  • Tryptophan
  • Triptorelin
  • Trimipramine
  • Trimeprazine
  • Triflupromazine
  • Trifluperidol
  • Trifluoperazine
  • Triazolam
  • Trazodone
  • Tramadol
  • Toremifene
  • Tolonium Chloride
  • Tizanidine
  • Tilidine
  • Thiothixene
  • Thiopropazate
  • Thiethylperazine
  • Tetrabenazine
  • Temazepam
  • Telithromycin
  • Telavancin
  • Tapentadol
  • Tacrolimus
  • Suvorexant
  • Sunitinib
  • Sulpiride
  • Sufentanil
  • Sotalol
  • Sorafenib
  • Solifenacin
  • Sodium Phosphate, Monobasic
  • Sodium Phosphate, Dibasic
  • Sodium Phosphate
  • Sodium Oxybate
  • Sevoflurane
  • Sertindole
  • Saquinavir
  • Salmeterol
  • Safinamide
  • Remoxipride
  • Remifentanil
  • Ranolazine
  • Ramelteon
  • Quinine
  • Quinidine
  • Quetiapine
  • Quazepam
  • Protriptyline
  • Propofol
  • Propafenone
  • Promethazine
  • Promazine
  • Prochlorperazine
  • Procainamide
  • Prazepam
  • Pitolisant
  • Piritramide
  • Pipotiazine
  • Piperacetazine
  • Pimavanserin
  • Perphenazine
  • Periciazine
  • Perflutren Lipid Microsphere
  • Perazine
  • Pentazocine
  • Pentamidine
  • Peginterferon Alfa-2b
  • Pazopanib
  • Pasireotide
  • Paregoric
  • Papaveretum
  • Panobinostat
  • Palonosetron
  • Paliperidone
  • Oxymorphone
  • Oxycodone
  • Oxazepam
  • Orphenadrine
  • Opium Alkaloids
  • Opium
  • Ondansetron
  • Olanzapine
  • Ofloxacin
  • Octreotide
  • Nortriptyline
  • Norfloxacin
  • Nitrous Oxide
  • Nitrazepam
  • Nilotinib
  • Nicomorphine
  • Nalbuphine
  • Nafarelin
  • Moxifloxacin
  • Morphine Sulfate Liposome
  • Morphine
  • Moricizine
  • Molindone
  • Mirtazapine
  • Mifepristone
  • Midazolam
  • Metronidazole
  • Methylene Blue
  • Methotrimeprazine
  • Methocarbamol
  • Methdilazine
  • Metaxalone
  • Meptazinol
  • Meprobamate
  • Meperidine
  • Melperone
  • Mefloquine
  • Meclizine
  • Lurasidone
  • Lumefantrine
  • Lorcaserin
  • Lorazepam
  • Levorphanol
  • Levomilnacipran
  • Levofloxacin
  • Leuprolide
  • Lapatinib
  • Ketobemidone
  • Ketazolam
  • Ketamine
  • Ivabradine
  • Isoflurane
  • Imipramine
  • Iloperidone
  • Idelalisib
  • Ibutilide
  • Hydroxychloroquine
  • Hydromorphone
  • Hydrocodone
  • Histrelin
  • Hexobarbital
  • Halothane
  • Haloperidol
  • Halofantrine
  • Halazepam
  • Granisetron
  • Goserelin
  • Gonadorelin
  • Gemifloxacin
  • Gatifloxacin
  • Fospropofol
  • Fluspirilene
  • Flurazepam
  • Fluphenazine
  • Fluoxetine
  • Flibanserin
  • Flecainide
  • Fingolimod
  • Fentanyl
  • Ethylmorphine
  • Ethopropazine
  • Ethchlorvynol
  • Eszopiclone
  • Estazolam
  • Escitalopram
  • Enflurane
  • Efavirenz
  • Duloxetine
  • Droperidol
  • Doxylamine
  • Donepezil
  • Domperidone
  • Dolasetron
  • Dofetilide
  • Disopyramide
  • Diphenoxylate
  • Diphenhydramine
  • Dihydrocodeine
  • Difenoxin
  • Dichloralphenazone
  • Diazepam
  • Diacetylmorphine
  • Dezocine
  • Dexmedetomidine
  • Desvenlafaxine
  • Deslorelin
  • Delavirdine
  • Delamanid
  • Degarelix
  • Dasatinib
  • Dantrolene
  • Dabrafenib
  • Cyclobenzaprine
  • Crizotinib
  • Conivaptan
  • Codeine
  • Clozapine
  • Clorazepate
  • Clonazepam
  • Clomipramine
  • Clobazam
  • Clarithromycin
  • Citalopram
  • Ciprofloxacin
  • Chlorzoxazone
  • Chlorpromazine
  • Chloroquine
  • Chlordiazepoxide
  • Chloral Hydrate
  • Ceritinib
  • Carphenazine
  • Carisoprodol
  • Cariprazine
  • Carbinoxamine
  • Butorphanol
  • Buspirone
  • Buserelin
  • Buprenorphine
  • Bromopride
  • Bromazepam
  • Boceprevir
  • Benperidol
  • Bedaquiline
  • Baclofen
  • Azithromycin
  • Astemizole
  • Asenapine
  • Artemether
  • Arsenic Trioxide
  • Aripiprazole
  • Apomorphine
  • Anileridine
  • Anagrelide
  • Amprenavir
  • Amoxapine
  • Amitriptyline
  • Amiodarone
  • Alprazolam
  • Almotriptan
  • Alfentanil
  • Acepromazine

Taking methadone at the same time as any of the drugs in the following list can increase your risk of certain side effects. However, it may be the best treatment option for you. If both drugs are to be used together, your health care professional may adjust the dose or frequency of use of one or both of the drugs:

  • Zidovudine
  • Voriconazole
  • Tipranavir
  • Thiotepa
  • Telaprevir
  • Stavudine
  • St John's Wort
  • Ritonavir
  • Risperidone
  • Rifampin
  • Peginterferon Alfa-2a
  • Nevirapine
  • Lopinavir
  • Fosamprenavir
  • Fluvoxamine
  • Etravirine
  • Didanosine
  • Desipramine
  • Atazanavir
  • Abacavir

Other interactions

You should not use some medicines around the time of eating food or particular food groups, as this could cause interactions to take place. Similarly, the use of tobacco or alcohol with certain drugs can also cause interactions. Before you begin using methadone, be sure to discuss this aspect of your treatment with your health care professional.

Medical interactions

Some historical or pre-existing medical conditions can affect how methadone works. Be sure to discuss your medical history with your treating physician before you start taking this medicine.

Methadone should be used with extreme caution by patients who have a history of any of the following conditions, as this drug can increase the risk of you suffering serious side effects:

  • Weakened physical condition
  • Stomach or bowel problems
  • Increased pressure in the head
  • Hypomagnesemia (low magnesium in the blood)
  • Hypokalemia (low potassium in the blood)
  • Heart rhythm problems (eg, arrhythmia, long QT syndrome)
  • Heart disease (eg, cardiac hypertrophy)
  • Head injuries
  • Gallbladder disease
  • Drug dependence, especially narcotic abuse or dependence
  • Depression
  • Breathing or lung problems, including chronic obstructive pulmonary disease (COPD), cor pulmonale, hypercapnia, hypoxia, and apnoea
  • Brain tumor
  • Alcohol abuse

Methadone should be used with caution in patients with the following conditions, as this drug may make these conditions worse:

  • Seizures
  • Pancreatitis (inflammation of the pancreas)
  • Hypotension (low blood pressure)

Patients who have a history of liver or kidney disease should be given an adjusted dose of methadone. This is because the drug's effects could be increased, due to slower removal of the medication from the body caused by these conditions.


When you decide to use any new medication, you should take into account the risks as well as the benefits of doing so. This decision should be taken following discussions with your health care professional. In the case of methadone, bear in mind the points mentioned in this section of the guide.

Be sure to mention to your health care professional if you have ever noticed any allergic reaction to methadone or any other drugs, including over the counter products, vitamin supplements, and herbal remedies. You should also mention if you have any known allergies to food colorants, preservatives, particular food groups, or animal by-products.

There have been no specific studies into the effects of methadone on children. It is not known whether it is safe and effective to use this medication to treat pediatric patients. Ask your health care professional for more advice if you have concerns in this regard.

Research carried out to date has not shown any problems that are specifically related to the treatment of old people with methadone. However geriatrics are more likely to suffer from age-related conditions, including liver, lung, kidney, and heart problems, which may necessitate caution and appropriate dosage adjustment.

It is not known whether using methadone can harm an unborn baby or result in its addiction to opioids at birth. If you are pregnant, you should discuss this risk with your health care professional before you start using methadone.

It is not known whether methadone can pass into a mother's breast milk and thus to a nursing infant where it could pose a risk. Discuss this aspect of childcare with your midwife or doctor before you start using methadone if you are breastfeeding.

You will be required to attend your health care professional for regular check-ups while you are using methadone. These visits will allow your GP to make sure that the drug is working as intended and to decide if you need to carry on using it.

Patients should be aware that methadone will add to the effects of other CNS depressants, including certain medications and alcohol, leaving you feeling drowsy and less alert than usual. Before you start using any of the following drugs, check with your health care professional:

  • Antihistamine
  • Cold and cough medicines
  • Sedatives
  • Sleeping drafts
  • Seizure medicines
  • Barbiturates
  • Anesthetics
  • Muscle relaxants
  • Narcotics

Methadone can be habit-forming, potentially resulting in mental or physical dependence. If you do not think that the medicine is working as effectively as it was when you first begin using it, do not increase your dose. Check with your health care professional for further instructions.

Note that using narcotic drugs for an extended period of time can cause severe constipation. In order to prevent this effect, your health care professional may recommend that you take laxatives, drink plenty of fluids, or eat more fiber. Long-term constipation can cause serious health problems, so be sure to follow your doctor's directions carefully.

Taking too much of this medication can lead to overdose, which may be life-threatening. The following are symptoms of overdose. If you think that you may have overdosed, summon emergency medical assistance right away:

  • Severe weakness or dizziness
  • Breathing difficulties
  • Slow heartbeat
  • Seizures
  • Clammy, cold skin

If you notice sudden changes in your heart rhythm, seek medical advice right away. You may begin to feel faint or dizzy, your heart rate may become uneven, pounding, or very fast. Tell your health care professional if you or anyone in your family has ever suffered from heart rhythm problems, including QT prolongation.

Methadone can cause dizziness, fainting, or feelings of lightheadedness when getting up from a seated or prone position. Try rising more slowly or laying down for a little while to help relieve these problems.

If you have been told to use methadone for a number of weeks or longer, you must not suddenly stop using it without checking with your health care professional first. You may be told to gradually lessen the dose before you stop taking the drug altogether, or to use another narcotic drug for a while to reduce the change of withdrawal side effects.

If you are due to have any medical tests, remember to tell the health care professional in charge that you are using methadone. This drug can affect the results of certain tests.

Methadone can cause drowsiness, dizziness, and feelings of lightheadedness. If you are affected in this way, do not drive, use machinery, or take part in any activity that could be dangerous if you are not fully alert.

Methadone can cause a condition called neonatal withdrawal syndrome in newborn babies. If your baby has diarrhea, irritability, abnormal sleep patterns, a high-pitched cry, tremors or shakiness, vomiting, weight loss, or failure to gain any weight, check with your health care professional right away.

You must not use any other medications while you are taking methadone, unless you have cleared their use with your health care professional first. This includes over the counter drugs, prescription medicines, herbal remedies, diet pills, or vitamin supplements.


Keep your prescription of methadone in its original container, closed and at room temperature. Do not place the medication close to sources of heat or in direct sunlight. Do not allow the drug to get wet. Do not freeze the medication.

Do not keep your methadone where children or pets could access it. If a pet does consume any of your medicine, you should consult your vet immediately. Strong narcotic pain drugs are not suitable for general use. Make sure that no other persons in your household use your methadone for pain relief purposes.

If the drug becomes out of date, or if you are no longer using it, ask your pharmacist or health care professional for advice on how to safely dispose of the medicine. Do not pour the drug down the toilet or drain. Never throw methadone tablets out with your trash where it could be found and eaten by animals or children.


Methadone is a narcotic opioid analgesic that is used to treat patients with severe to moderate pain. The drug is designed to provide 24/7 pain relief; it is not to be used as a quick fix for minor headaches etc.

Patients should be aware that methadone can become addictive. Together with medical supervision and counseling, methadone is also used to treat addiction to heroin and other opioid drugs.

Note that methadone will not cure your illness or health condition, but it can be very effective in taking away the severe pain the condition causes.

Methadone interacts adversely with a very wide range of other medications and can be dangerous to people with certain existing health conditions. Discuss your medical history in full with your doctor before you start using this medicine, and be sure to attend for regular check-ups throughout your course of treatment.