Combining Fentanyl and Tizanidine is a major interaction and should generally be avoided without close medical supervision.
Patients may experience severe respiratory depression, characterized by decreased respiratory rate and depth, potentially leading to hypoxemia and hypercapnia. Other clinical effects include profound sedation, excessive somnolence, dizziness, impaired psychomotor function, and hypotension. This combination significantly increases the risk of falls, accidental injury, and life-threatening respiratory compromise.
Mechanism: Both fentanyl, an opioid agonist, and tizanidine, an alpha-2 adrenergic agonist muscle relaxant, exert significant central nervous system (CNS) depressant effects. Their co-administration leads to an additive pharmacological effect, increasing the overall CNS depression. This synergistic action primarily affects neuronal excitability and neurotransmitter release, leading to profound sedation and respiratory depression.
Fentanyl vs. Tizanidine
Compare Fentanyl and Tizanidine: mechanism of action, indications, side effects, cost, and which may be right for you.
Quick Comparison
| Category | Fentanyl | Tizanidine |
|---|---|---|
| Drug Class | Opioid Analgesics | Skeletal Muscle Relaxants |
| Rx Status | Rx | Rx |
| Generic Available | No | No |
| Typical Cost | $150–$600/month | $4–$25/month |
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 →Tizanidine Overview
Tizanidine is a medication used to relax muscles and reduce muscle stiffness or spasms (spasticity). It works by acting on the nervous system to calm overactive nerve signals that cause muscles to tighten. This helps improve muscle movement and comfort for daily activities.
Full Tizanidine 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.
Tizanidine
Tizanidine is a central alpha-2-adrenergic receptor agonist and presumably reduces spasticity by increasing presynaptic inhibition of motor neurons. The effects of tizanidine are greatest on polysynaptic pathways. The effect of these actions is thought to reduce facilitation of spinal motor neurons.
Approved Uses (Indications)
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…
Tizanidine
Tizanidine Tablets, USP is a central alpha-2-adrenergic agonist indicated for the management of spasticity. Because of the short duration of therapeutic effect, treatment with Tizanidine Tablets, USP should be reserved for those daily activities and times when relief of spasticity is most important [see Dosage and Administration ]. Tizanidine Tablets, USP is a central alpha-2-adrenergic agonist indicated for the management of spasticity. Because of the short duration of therapeutic effect, treatment with Tizanidine Tablets, USP should be reserved for those daily ac…
Side Effects
Fentanyl
Tizanidine
Cost Comparison
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.
Tizanidine
$4–$25/month
Tizanidine is available as an affordable generic. Patients can often find significant savings by using discount cards like GoodRx or checking prices at different pharmacies.
Compare prices for Fentanyl and Tizanidine
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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.