Methadone and Cyclobenzaprine Interaction

Drug interaction information between Methadone and Cyclobenzaprine.

Methadone and Cyclobenzaprine have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Methadone and Cyclobenzaprine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Methadone

Opioid Agonist

Drug B

Cyclobenzaprine

Muscle Relaxant

How They Interact

These medications both affect serotonin levels and can cause a serious reaction when used together.

FDA Label Information

Examples: Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, drugs that effect the serotonin neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), certain muscle relaxants (i.e., cyclobenzaprine, metaxalone), monoamine oxidase (MAO) inhibitors (those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue). Examples: cyclobenzaprine, metaxalone Diuretics Clinical Impact: Opioids can reduce the efficacy...

Frequently Asked Questions

What SPL severity band is on file for Methadone + Cyclobenzaprine?

Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Methadone has 41 labeled pairs on file vs Cyclobenzaprine's 17. In the minor band specifically: Methadone has 37 (also Gabapentin, Sertraline, Trazodone, Tramadol); Cyclobenzaprine has 14 (also Acetaminophen/Oxycodone, Buprenorphine, Buprenorphine/Naloxone, Buprenorphine).

What mechanism field is on file for Methadone and Cyclobenzaprine?

These medications both affect serotonin levels and can cause a serious reaction when used together.

Methadone carries more major-labeled pairs than Cyclobenzaprine

SPL source-record counts only. This page's band is minor · classes on file: Methadone (Opioid Agonist); Cyclobenzaprine (Muscle Relaxant).

Methadone has 2 major-labeled pairs vs Cyclobenzaprine's 0. This page itself is in the minor band, not the major band.

Methadone

2 major · 2 moderate · 37 minor · 41 total

Cyclobenzaprine

0 major · 3 moderate · 14 minor · 17 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.