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Drug interactions between methadone and methamphetamine

Results for the following 2 drugs:

Interactions between your drugs


methadone methamphetamine

Applies to: methadone and methamphetamine

Consumer information for this interaction is not currently available.

MONITOR: Coadministration of amphetamines and amphetamine-like drugs with certain opioids or the synthetic opioid derivative, dextromethorphan, may increase the risk of serotonin syndrome. Dextromethorphan and some opioids, particularly those in the phenylpiperidine class, are weak serotonin reuptake inhibitors whose effects may be potentiated by amphetamines. However, clinical data are limited. Case reports of serotonin syndrome involving these agents have primarily been associated with concomitant use of highly serotonergic substances such as selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, monoamine oxidase inhibitors, and other antidepressants. Rarely, except in the case of abuse or overdose, has serotonin syndrome been associated with the use of amphetamines, opioids, or dextromethorphan alone or with each other. In the case of amphetamines, serotonin syndrome has most frequently been reported with the use of MDMA, or ecstasy, an amphetamine derivative with enhanced serotonergic activity over classical amphetamines, which tend to be more dopaminergic. Serotonin syndrome is a rare but serious and potentially fatal condition thought to result from hyperstimulation of 5-HT1A and 2A receptors in the brainstem and peripheral nervous system. Symptoms may include mental status changes such as irritability, altered consciousness, confusion, hallucination, and coma; autonomic dysfunction such as tachycardia, hyperthermia, diaphoresis, shivering, blood pressure lability, and mydriasis; neuromuscular abnormalities such as hyperreflexia, myoclonus, tremor, rigidity, and ataxia; and gastrointestinal symptoms such as abdominal cramping, nausea, vomiting, and diarrhea.

MANAGEMENT: Caution is recommended when amphetamines and amphetamine-like drugs are used with dextromethorphan or opioids with serotonergic effects such as fentanyl, meperidine, methadone, propoxyphene, and tramadol. Patients should be monitored for symptoms of the serotonin syndrome during treatment. Particular caution is advised when increasing the dosages of these agents. If serotonin syndrome develops or is suspected during the course of therapy, all serotonergic agents should be discontinued immediately and supportive care rendered as necessary. Moderately ill patients may also benefit from the administration of a serotonin antagonist (e.g., cyproheptadine, chlorpromazine). Severe cases should be managed under consultation with a toxicologist and may require sedation, neuromuscular paralysis, intubation, and mechanical ventilation in addition to the other measures.


  1. Mugele J, Nanagas KA, Tormoehlen LM "Serotonin Syndrome Associated With MDPV Use: A Case Report." Ann Emerg Med (2012):
  2. Gillman PK "Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity." Br J Anaesth (2005):
  3. "Product Information. Nuedexta (dextromethorphan-quinidine)." Avanir Pharmaceuticals, Inc, Aliso Viejo, CA.
  4. "Product Information. Adderall (amphetamine-dextroamphetamine)" Shire Richwood Pharmaceutical Company, Florence, KY.
  5. "Product Information. Sanorex (mazindol)" Novartis Pharmaceuticals, East Hanover, NJ.
  6. "Product Information. Desoxyn (methamphetamine)" Abbott Pharmaceutical, Abbott Park, IL.
  7. Lee J, Franz L, Goforth HW "Serotonin syndrome in a chronic-pain patient receiving concurrent methadone, ciprofloxacin, and venlafaxine." Psychosomatics 50 (2009): 638-9
  8. "Product Information. Vyvanse (lisdexamfetamine)." Shire US Inc, Florence, KY.
  9. Hunter B, Kleinert MM, Osatnik J, Soria E "Serotonergic syndrome and abnormal ocular movements: worsening of rigidity by remifentanil?" Anesth Analg 102 (2006): 1589
  10. "Product Information. Adipex-P (phentermine)." Teva Pharmaceuticals (formerly Gate Pharmaceuticals), Sellersville, PA.
  11. Davis JJ, Buck NS, Swenson JD, Johnson KB, Greis PE "Serotonin syndrome manifesting as patient movement during total intravenous anesthesia with propofol and remifentanil." J Clin Anesth 25 (2013): 52-4
View all 11 references

Drug and food interactions


methadone food

Applies to: methadone

Grapefruit juice can increase the blood levels and effects of methadone. If you regularly consume grapefruits or grapefruit juice, you should be monitored for side effects and/or changes in methadone levels. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor. Orange juice is not expected to interact.

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methamphetamine food

Applies to: methamphetamine

Using methamphetamine with alcohol can increase the risk of cardiovascular side effects such as increased heart rate, chest pain, or blood pressure changes. In addition, you may also be more likely to experience nervous system side effects such as dizziness, drowsiness, depression, and difficulty concentrating. You should avoid or limit the use of alcohol while being treated with methamphetamine. Do not use more than the recommended dose of methamphetamine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medication without first talking to your doctor.

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Therapeutic duplication warnings

No therapeutic duplications were found for your selected drugs.

Drug Interaction Classification

The classifications below are a guideline only. The relevance of a particular drug interaction to a specific patient is difficult to determine using this tool alone given the large number of variables that may apply.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No information available.

Do not stop taking any medications without consulting your healthcare provider.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.