cyclobenzaprine vs fentanyl
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Side-by-side comparison of cyclobenzaprine and fentanyl. 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).
Flexeril, Amrix
Duragesic, Actiq
Cyclobenzaprine is a muscle relaxant. It helps relieve muscle spasms and pain.
Fentanyl Citrate Injection is a strong opioid pain medicine. It is used to provide short-term pain relief, often during and after surgery.
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.
Fentanyl Citrate Injection is used to manage pain during and after surgery. It can be used alone or with other medicines during general or regional anesthesia. It may also be used with oxygen for high-risk patients during certain surgeries.
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.
Fentanyl is an opioid that works by binding to receptors in the brain and spinal cord. This binding decreases the feeling of pain. It can also cause sleepiness and slow breathing.
- • Drowsiness
- • Dry mouth
- • Fatigue
- • Headache
- • Nausea
- • Vomiting
- • Dizziness
- • Blurred vision
- Pain 4,871
- Fatigue 3,808
- Nausea 3,303
- Headache 3,292
- Chronic Kidney Disease 2,749
- Drug Abuse 10,453
- Pain 7,250
- Drug Dependence 6,027
- Toxicity To Various Agents 5,846
- Overdose 5,720
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.
Fentanyl Citrate Injection can cause serious and life-threatening risks: * Addiction, abuse, and misuse can lead to overdose and death. Your doctor will assess your risk before prescribing and monitor you regularly. * Life-threatening respiratory depression (slowed or stopped breathing) can occur, especially when starting the medicine or after a dose increase. Proper dosing is essential. * Taking fentanyl with benzodiazepines (like Valium or Xanax) or other CNS depressants (including alcohol) can cause severe sleepiness, slowed breathing, coma, and death. This combination should be avoided unless there are no other options. * Using fentanyl with certain other medicines (CYP3A4 inhibitors or inducers) can change the amount of fentanyl in your blood, leading to dangerous side effects or withdrawal symptoms. Your doctor will monitor you closely if these medicines are used together.
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.
Using fentanyl for a long time during pregnancy can cause withdrawal symptoms in the newborn. Fentanyl is not recommended during labor or delivery because it can cause breathing problems in the baby.
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How to Read This cyclobenzaprine vs fentanyl Comparison
cyclobenzaprine is classified in the Muscle Relaxant drug class, while fentanyl 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 fentanyl has 35,296. 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 both drugs increase the level of a brain chemical called serotonin. taking them together can cause too much serotonin to build up in your body, which can be dangerous.. 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 fentanyl.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.