Cyclobenzaprine

type of chemical entity
Subclass of	chemical compound
Get use	Medication
Chemical formula	C₂₀H₂₁N
Canonical SMILES	CN(C)CCC=C1C2=CC=CC=C2C=CC3=CC=CC=C31, CN(C)CCC=C1c2ccccc2C=Cc3c1cccc3
Active ingredient in	Fexmid, Flexeril, Amrix
Side effect	headache
LiverTox likelihood score	Լյարդի ախտահարման հավանականության E կատեգորիա
Subject has role	tricyclic antidepressant, central muscle relaxants, tranquilizer, muscle relaxant

Cyclobenzaprine, dem sell under chaw brand names wey dey include, historically, Flexeril, be a muscle relaxer dem use give muscle spasms from musculoskeletal conditions of sudden onset.^[1] E no be useful insyd cerebral palsy.^[1] Dem dey take am by mouth.^[1]

Common side effects dey include headache, tiredness, dizziness, den dry mouth.^[1] Serious side effects fi include an irregular heartbeat.^[1] Der be no evidence of harm insyd pregnancy, buh na e no be well studied insyd dis population.^[1] E for no be used togeda plus MAOIs.^[1] How e dey work be unclear.^[1] Insyd any case, e be known to inhibit serotonin den norepinephrine reuptake den to block serotonin, adrenergic, histamine, den muscarinic acetylcholine receptors.^[2]^[3] Chemically, e be very similar to tricyclic antidepressants like amitriptyline.^[2]

Na dem approve cyclobenzaprine for medical use insyd de United States insyd 1977.^[1] E be available by prescription as a generic medication.^[1] Insyd 2023, na e be de 47th most commonly prescribed medication insyd de United States, plus more dan 13 million prescriptions.^[4]^[5] Na e no be available insyd de United Kingdom as of 2012.^[6]

References

1 2 3 4 5 6 7 8 9 10 "Cyclobenzaprine Monograph for Professionals". Drugs.com. AHFS. Retrieved 22 December 2018.
1 2 Mestres J, Seifert SA, Oprea TI (November 2011). "Linking pharmacology to clinical reports: cyclobenzaprine and its possible association with serotonin syndrome". Clin Pharmacol Ther. 90 (5): 662–665. doi:10.1038/clpt.2011.177. PMC 3809033. PMID 21975349.
↑ Daugherty B, Gershell L, Lederman S (October 2012). "Cyclobenzaprine (CBP) and Its Major Metabolite Norcyclobenzaprine (nCBP) Are Potent Antagonists of Human Serotonin Receptor 2a (5HT2a), Histamine Receptor H-1 and α-Adrenergic Receptors: Mechanistic and Safety Implications for Treating Fibromyalgia Syndrome by Improving Sleep Quality". Arthritis and Rheumatism. 64 (10): S416. In vitro, CBP and nCBP exhibited high affinity binding (Ki) to receptors: 5HT2a (5.2 and 13 nM, respectively) and 5HT2c (5.2 and 43 nM), adrenergic α-1A (5.6 and 34 nM), α-2B (Ki = 21 and 150 nM) and α-2C (Ki = 21 and 48 nM,); H1 (1.3 and 5.6 nM); and M1 (7.9 and 30 nM). Like CBP, nCBP is a functional antagonist at 5HT2a (IC50 = 92 nM) by Ca+ mobilization. CBP is also an antagonist on 5HT2b (IC50 = 100 nM). CBP and nCBP are functional antagonists on 5HT2c (IC50 = 0.44 and 1.22 μM) and on α-2A (IC50 = 4.3 and 6.4 μM). In contrast, both CBP and nCBP are functional agonists on 5HT1a (EC50= 5.3 and 3.2 μM). [...] CPB and nCBP are potent antagonists of 5HT2a, 5HT2b, H-1, adrenergic α-1A, α-2B and α-2C receptors.
↑ "Top 300 of 2023". ClinCalc. Archived from the original on 12 August 2025. Retrieved 12 August 2025.
↑ "Cyclobenzaprine Drug Usage Statistics, United States, 2013 - 2023". ClinCalc. Retrieved 18 August 2025.
↑ "Fibromyalgia, psychiatric comorbidity, and the somatosensory cortex". British Journal of Medical Practitioners. 5 (2): a522. 2012.

External links

[AHFS2018-1] 1 2 3 4 5 6 7 8 9 10 "Cyclobenzaprine Monograph for Professionals". Drugs.com. AHFS. Retrieved 22 December 2018.

[MestresSeifertOprea2011-2] 1 2 Mestres J, Seifert SA, Oprea TI (November 2011). "Linking pharmacology to clinical reports: cyclobenzaprine and its possible association with serotonin syndrome". Clin Pharmacol Ther. 90 (5): 662–665. doi:10.1038/clpt.2011.177. PMC 3809033. PMID 21975349.

[DaughertyGershellLederman2012-3] Daugherty B, Gershell L, Lederman S (October 2012). "Cyclobenzaprine (CBP) and Its Major Metabolite Norcyclobenzaprine (nCBP) Are Potent Antagonists of Human Serotonin Receptor 2a (5HT2a), Histamine Receptor H-1 and α-Adrenergic Receptors: Mechanistic and Safety Implications for Treating Fibromyalgia Syndrome by Improving Sleep Quality". Arthritis and Rheumatism. 64 (10): S416. In vitro, CBP and nCBP exhibited high affinity binding (Ki) to receptors: 5HT2a (5.2 and 13 nM, respectively) and 5HT2c (5.2 and 43 nM), adrenergic α-1A (5.6 and 34 nM), α-2B (Ki = 21 and 150 nM) and α-2C (Ki = 21 and 48 nM,); H1 (1.3 and 5.6 nM); and M1 (7.9 and 30 nM). Like CBP, nCBP is a functional antagonist at 5HT2a (IC50 = 92 nM) by Ca+ mobilization. CBP is also an antagonist on 5HT2b (IC50 = 100 nM). CBP and nCBP are functional antagonists on 5HT2c (IC50 = 0.44 and 1.22 μM) and on α-2A (IC50 = 4.3 and 6.4 μM). In contrast, both CBP and nCBP are functional agonists on 5HT1a (EC50= 5.3 and 3.2 μM). [...] CPB and nCBP are potent antagonists of 5HT2a, 5HT2b, H-1, adrenergic α-1A, α-2B and α-2C receptors.

[Top300Drugs-4] "Top 300 of 2023". ClinCalc. Archived from the original on 12 August 2025. Retrieved 12 August 2025.

[5] "Cyclobenzaprine Drug Usage Statistics, United States, 2013 - 2023". ClinCalc. Retrieved 18 August 2025.

[6] "Fibromyalgia, psychiatric comorbidity, and the somatosensory cortex". British Journal of Medical Practitioners. 5 (2): a522. 2012.

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