Last reviewed · How we verify
cyclobenzaprine ER (AMRIX)
Cyclobenzaprine is a centrally acting muscle relaxant that reduces muscle tension by depressing activity in the brainstem.
Cyclobenzaprine is a centrally acting muscle relaxant that reduces muscle tension by depressing activity in the brainstem. Used for Muscle spasm associated with acute musculoskeletal conditions, Muscle spasticity in chronic conditions.
At a glance
| Generic name | cyclobenzaprine ER (AMRIX) |
|---|---|
| Also known as | AMRIX |
| Sponsor | State University of New York - Upstate Medical University |
| Drug class | Muscle relaxant (centrally acting) |
| Target | Brainstem monoamine receptors (non-selective); structurally related to tricyclic antidepressants |
| Modality | Small molecule |
| Therapeutic area | Neurology / Musculoskeletal |
| Phase | FDA-approved |
Mechanism of action
Cyclobenzaprine works primarily through central nervous system depression, acting on the brainstem to reduce muscle tone and spasticity. It is structurally related to tricyclic antidepressants and may work through noradrenergic pathways. The extended-release (ER) formulation allows for once-daily dosing with sustained therapeutic levels.
Approved indications
- Muscle spasm associated with acute musculoskeletal conditions
- Muscle spasticity in chronic conditions
Common side effects
- Drowsiness
- Dizziness
- Dry mouth
- Fatigue
- Headache
Key clinical trials
- Cyclobenzaprine Extended Release (ER) for Fibromyalgia (PHASE4)
- Steady-State Pharmacokinetic Comparison Study of TNX-102 SL 5.6 mg Versus AMRIX® 30 mg ER Capsules (PHASE1)
- Medication Effects on Periurethral Sensation,Urethral Sphincter Activity and Pressure Flow Parameters (NA)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape: