Cyclobenzaprine
Systematic (IUPAC) name
3-(5H-dibenzo[a,d]cyclohepten-5-ylidene)- N,N-dimethyl-1-propanamine
Identifiers
CAS number	303-53-7
ATC code	M03BX08
PubChem	2895
DrugBank	APRD00213
Chemical data
Formula	C20H21N
Mol. weight	275.387 g/mol
Pharmacokinetic data
Bioavailability	33% to 55%
Metabolism	?
Half life	18 hours (range 8-37 hours; n=18)
Excretion	?
Therapeutic considerations
Pregnancy cat.	Category B Image File history File links Cyclobenzaprine. ... IUPAC nomenclature is a systematic way of naming organic chemical compounds. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences and alloys. ... The Anatomical Therapeutic Chemical Classification System is used for the classification of drugs. ... A section of the Anatomical Therapeutic Chemical Classification System. ... PubChem is a database of chemical molecules . ... DrugBank is a database available at the University of Alberta that provides information about thousands of products. ... A chemical formula (also called molecular formula) is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... The molecular mass of a substance (less accurately called molecular weight and abbreviated as MW) is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of carbon-12). ... In pharmacology, bioavailability is used to describe the fraction of an administered dose of medication that reaches the systemic circulation, one of the principal pharmacokinetic properties of drugs. ... Overview of the citric acid cycle The citric acid cycle, one of the central metabolic pathways in aerobic organisms. ... The elimination half-life of a drug (or any xenobiotic agent) refers to the timecourse necessary for the quantity of the xenobiotic agent in the body (or plasma concentration) to be reduced to half of its original level through various elimination processes. ... Excretion is the process of eliminating waste products of metabolism and other materials that are of no use. ... The pregnancy category of a pharmaceutical agent is an assessment of the risk of fetal injury due to the pharmaceutical, if it is used as directed by the mother during pregnancy. ...
Legal status	Unscheduled The regulation of therapeutic goods, that is drugs and therapeutic devices, varies by jurisdiction. ...
Routes	?

Cyclobenzaprine is a skeletal muscle relaxant and a central nervous system (CNS) depressant. It is marketed as Flexeril (5 and 10 mg tablets). Both the 5 and 10 milligram tablets are available generically. In pharmacology and toxicology, a route of administration is the path by which a drug, fluid, poison or other substance is brought into contact with the body 1. ... A muscle relaxant is a drug which decreases the tone of a muscle. ... See also sedative. ...

Mechanism of action

The exact mechanism of action for cyclobenzaprine is unknown. Current research appears to indicate that cyclobenzaprine acts on the locus coeruleus where it results in increased norepinephrine release, potentially through the gamma fibers which innervate and inhibit the alpha motor neurons in the ventral horn of the spinal cord.[1] Decreased firing of the alpha motor neuron results in decreased muscular tone. Wikipedia does not yet have an article with this exact name. ... The Locus ceruleus, also spelled locus coeruleus, (Latin for the blue bit) is a nucleus in the brain stem apparently responsible for the physiological reactions involved in stress and panic. ... Alpha motor neurons (α-MNs) are large lower motor neurons of the brainstem and spinal cord. ...

Indications

Cyclobenzaprine is typically prescribed to relieve pain and muscle spasms. Typically, muscle spasms occur in an injury to stabilize the affected body part and prevent further damage. The spasm of the muscles can increase the pain level. It is believed that by decreasing muscular spasm, pain is diminished. A common application would be that of a whiplash injury in a car accident. Muscle relaxants such as Cyclobenzaprine (Flexeril) and Orphenadrine Citrate (Norflex) have also been studied in the treatment of fibromyalgia. In a study of 120 fibromyalgia patients, those receiving Cyclobenzaprine (10 to 40 mg) over a 12 week period had significantly improved quality of sleep and pain score. There was a trend towards improvement in fatigue symptoms but not in duration of morning stiffness. Interestingly, there was also a reduction in the total number of tender points and muscle tightness. Whiplash is the result of impulsive stretching of the spine, often the result of a rear-end collision between cars or trucks. ...

It is also prescribed off-label as a sleep-aid. The term off-label refers to the use of a drug for a medical condition other than for which it was officially approved and marketed. ... A sedative is a drug that depresses the central nervous system (CNS), which causes calmness, relaxation, reduction of anxiety, sleepiness, slowed breathing, slurred speech, staggering gait, poor judgment, and slow, uncertain reflexes. ...

Side effects

Common side effects include drowsiness, dizziness, and blurred vision. Other side effects are respiratory depression and decreased functionality in various muscles. Long term use has been associated with vision damage.

Interactions

When you are taking cyclobenzaprine, it is especially important that your health care professional know if you are taking any of the following:

• Alcohol or
• Central nervous system (CNS) depressants (medicines that cause drowsiness) or
• Tricyclic antidepressants (amitriptyline [e.g., Elavil], amoxapine [e.g., Asendin], clomipramine [e.g., Anafranil], desipramine [e.g., Pertofrane], doxepin [e.g., Sinequan], imipramine [e.g., Tofranil], nortriptyline [e.g., Aventyl], protriptyline [e.g., Vivactil], trimipramine [e.g., Surmontil])—The chance of side effects may be increased
• Monoamine oxidase (MAO) inhibitors (furazolidone [e.g., Furoxone], phenelzine [e.g., Nardil], procarbazine [e.g., Matulane], selegiline (e.g., Eldepryl), tranylcypromine [e.g., Parnate])—Taking cyclobenzaprine while you are taking or within 2 weeks of taking MAO inhibitors may increase the chance of side effects

Legality

Cyclobenzaprine is regulated in the U.S. for prescription use only. Cyclobenzaprine does not fall within most governmental guidelines as a controlled narcotic, however possession without a valid / current prescription may be illegal depending upon various state and local laws. A medical prescription ) is an order (often in written form) by a qualified health care professional to a pharmacist or other therapist for a treatment to be provided to their patient. ...

Abuse

Cyclobenzaprine is not widely abused, despite having an arguably high potential for abuse.

When used for illicit purposes, the drug is often referred to as "cyclone" with recreational doses ranging from 20 to 80 mg. At these dosages, users report mild to moderate drowsiness and relaxation as the primary effects. Compared with other commonly abused CNS depressants, cyclobenzaprine's effects are considered to be mild, limiting its popularity as a recreational drug.

Cyclobenzaprine, on the other hand, can induce moderate to severe anticholinergic effects at higher doses, as well as benzodiazepine-like sedation and often pleasurable muscle-relaxation. At even higher doses, cyclobenzaprine may cause severe ataxia, and due to excessive muscle-relaxation, and possibly disorienting side effects such as a floating sensation or other imagined movements (usually experienced when at rest.) An anticholinergic agent is a member of a class of pharmaceutical compounds which serve to reduce the effects mediated by acetylcholine in the central nervous system and peripheral nervous system. ... Alprazolam 2mg tablets The benzodiazepines (pronounced , or benzo for short) are considered minor tranquilizers that are a class of drugs with sedative, hypnotic, anxiolytic, anticonvulsant, amnestic and muscle relaxant properties. ... Ataxia (from Greek ataxiā, meaning failure to put in order) is unsteady and clumsy motion of the limbs or torso due to a failure of the gross coordination of muscle movements. ...

Overdose

Although purportedly unpleasant, cyclobenzaprine is relatively benign in case of overdose, depending on its toxicity level in the user, and also on the susceptibility of the user to possibly harmful effects of overdose. Note that the susceptibility to these potentially damaging effects is greatly increased when cyclobenzaprine is used in conjunction with other drugs, particularly Central Nervous System Depressants and other antidepressants. Use of cyclobenzaprine with a MAOI (Mono Amine Oxidase Inhibitor) will very possibly result in fatality. See also sedative. ... Monoamine oxidase inhibitors (MAOIs) are a class of antidepressant drugs prescribed for the treatment of depression. ...

External links

• Erowid Cyclobenzaprine Vault