cyclobenzaprine vs morphine
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Side-by-side comparison of cyclobenzaprine and morphine. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
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 Cimetidine Clinical Impact: The concomitant use of morphine...
Flexeril, Amrix
MS Contin, Kadian
Cyclobenzaprine is a muscle relaxant. It helps relieve muscle spasms and pain.
Morphine is a strong pain medicine. It is used to treat severe pain that needs an opioid medicine when other treatments don't work well enough.
This medicine treats muscle spasms caused by painful conditions. It is meant to be used with rest and physical therapy. It should only be used for a short time, usually 2 to 3 weeks.
Morphine is used to manage severe pain in adults and children who weigh at least 110 pounds. It is for pain that requires an opioid medicine. It is used when other pain treatments are not strong enough or cannot be tolerated.
Cyclobenzaprine works in the brain and spinal cord to relax your muscles. It reduces muscle spasms, which helps to relieve pain and improve movement. It does not directly work on the muscles themselves.
Morphine works by attaching to receptors in the brain and spinal cord. These receptors are involved in sending pain signals. By binding to these receptors, morphine blocks pain signals and reduces pain.
- • Drowsiness
- • Dry mouth
- • Fatigue
- • Headache
- • Constipation
- • Nausea
- • Feeling sleepy
- • Lightheadedness
- • Dizziness
- Pain 4,871
- Fatigue 3,808
- Nausea 3,303
- Headache 3,292
- Chronic Kidney Disease 2,749
- Pain 5,858
- Nausea 5,536
- Vomiting 4,337
- Death 4,306
- Fatigue 4,130
You should not take this medicine if you are allergic to any of its ingredients. You should not take this medicine if you are taking a monoamine oxidase (MAO) inhibitor or have taken one in the past 14 days. Taking cyclobenzaprine with an MAO inhibitor can cause serious problems, including seizures and death. Also, do not take it if you have heart problems or an overactive thyroid.
Morphine can cause addiction, abuse, and misuse, which can lead to overdose and death. It can also cause life-threatening breathing problems, especially when you start taking it or after a dose increase. Accidental ingestion, especially by children, can cause a fatal overdose. Taking morphine with benzodiazepines or other CNS depressants (including alcohol) can cause severe sedation, breathing problems, coma, and death. If you use morphine for a long time during pregnancy, your baby could have withdrawal symptoms after birth.
It is not known if cyclobenzaprine can harm an unborn baby. Talk to your doctor if you are pregnant, planning to become pregnant, or breastfeeding.
Morphine may harm your unborn baby. Using morphine for a long time during pregnancy can cause withdrawal symptoms in the newborn. Tell your doctor if you are pregnant or plan to become pregnant.
Also Compare, Nearby Drugs
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How to Read This cyclobenzaprine vs morphine Comparison
cyclobenzaprine is classified in the Muscle Relaxant drug class, while morphine sits within the Opioid Analgesic class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, cyclobenzaprine has 18,023 submissions while morphine has 24,167. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to this muscle relaxant affects the serotonin system in your body. when combined with morphine, it can increase the risk of a dangerous condition called serotonin syndrome.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for cyclobenzaprine or morphine.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.