Combining Chlorzoxazone and Fentanyl is a major interaction and should generally be avoided without close medical supervision.
Concomitant use can result in profound sedation, respiratory depression, hypotension, and psychomotor impairment. Patients may experience dizziness, confusion, and difficulty with coordination, increasing the risk of falls and accidents. In severe cases, this interaction can lead to respiratory arrest and death.
Mechanism: Fentanyl, an opioid analgesic, primarily acts on mu-opioid receptors in the central nervous system (CNS) to produce analgesia and respiratory depression. Chlorzoxazone, a centrally acting skeletal muscle relaxant, also exerts its effects through CNS depression, likely by inhibiting polysynaptic reflexes at the spinal cord and subcortical levels. The co-administration of these agents leads to an additive depressant effect on the CNS.
Chlorzoxazone vs. Fentanyl
Compare Chlorzoxazone and Fentanyl: mechanism of action, indications, side effects, cost, and which may be right for you.
Drug A
Chlorzoxazone
Chlorzoxazone
Skeletal Muscle Relaxants
RxDrug B
Fentanyl
Fentanyl
Opioid Analgesics
RxQuick Comparison
| Category | Chlorzoxazone | Fentanyl |
|---|---|---|
| Drug Class | Skeletal Muscle Relaxants | Opioid Analgesics |
| Rx Status | Rx | Rx |
| Generic Available | No | No |
| Typical Cost | $50–$150/month | $150–$600/month |
Chlorzoxazone Overview
Chlorzoxazone is a medication used to help relieve discomfort from sudden, painful muscle and bone conditions. It works by affecting the central nervous system, which helps reduce pain and muscle spasms, often alongside rest and physical therapy.
Full Chlorzoxazone guide →Fentanyl Overview
FENTANYL (brand name: FENTANYL) is a Opioid Analgesics. 1 INDICATIONS AND USAGE Fentanyl transdermal system is indicated for the management of severe and persistent pain in opioid-tolerant patients, that requires an opioid analgesic and that cannot be adequately treated with alternative options, including immediate-release opioids. Patients considered…
Full Fentanyl guide →How Each Drug Works
Fentanyl
Fentanyl is an opioid agonist. Fentanyl interacts predominately with the opioid mu-receptor. These mu-binding sites are distributed in the human brain, spinal cord, and other tissues.
Approved Uses (Indications)
Chlorzoxazone
INDICATIONS AND USAGE Chlorzoxazone is indicated as an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute, painful musculoskeletal conditions. The mode of action of this drug has not been clearly identified, but may be related to its sedative properties. Chlorzoxazone does not directly relax tense skeletal muscles in man.
Fentanyl
Fentanyl transdermal system is indicated for the management of severe and persistent pain in opioid-tolerant patients, that requires an opioid analgesic and that cannot be adequately treated with alternative options, including immediate-release opioids. Patients considered opioid-tolerant are those who are taking, for one week or longer, at least 60 mg morphine per day, 25 mcg transdermal fentanyl per hour, 30 mg oral oxycodone per day, 8 mg oral hydromorphone per day, 25 mg oral oxymorphone per day, 60 mg oral hydrocodone per day, or an equianalgesic dose of another op…
Side Effects
Chlorzoxazone
Fentanyl
Cost Comparison
Chlorzoxazone
$50–$150/month
As a brand-only medication, Chlorzoxazone can be expensive. Patients should check for manufacturer coupons or patient assistance programs, and compare prices at different pharmacies using discount cards.
Fentanyl
$150–$600/month
As a brand-only medication, fentanyl can be expensive. Patients should check for manufacturer coupons or patient assistance programs, and compare prices at different pharmacies using discount cards.
Compare prices for Chlorzoxazone and Fentanyl
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Medical Disclaimer
The information on RxGuide is intended for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician, pharmacist, or other qualified health provider with any questions you may have regarding a medical condition or medication. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.