See the DrugPatentWatch profile for Flexeril
What is Flexeril and What Does It Treat?
Flexeril is a brand name for cyclobenzaprine, a muscle relaxant used to treat muscle spasms. It is typically prescribed for short-term relief of discomfort associated with acute, painful musculoskeletal conditions [1].
How Does Flexeril Work?
The exact mechanism of cyclobenzaprine is not fully understood, but it is thought to act on the central nervous system. It is believed to reduce muscle spasms by influencing descending monoaminergic pathways that control motor neurons [1].
What are the Common Side Effects of Flexeril?
Common side effects of Flexeril include drowsiness, dizziness, dry mouth, fatigue, and headache [1].
What Drug Interactions Should I Be Aware Of With Flexeril?
Flexeril can interact with several types of medications, potentially leading to serious adverse effects.
Interactions with CNS Depressants
Combining Flexeril with central nervous system (CNS) depressants, such as alcohol, barbiturates, benzodiazepines, and other sedative medications, can increase CNS depression. This can lead to extreme drowsiness, respiratory depression, coma, and death [1].
Interactions with MAO Inhibitors
Flexeril should not be used within 14 days of taking monoamine oxidase (MAO) inhibitors or within 14 days of discontinuing an MAO inhibitor. This combination can lead to hyperpyretic crisis and severe reactions, including seizures, and potentially death [1].
Interactions with Anticholinergic Drugs
Due to its own anticholinergic properties, Flexeril may have additive effects when taken with other anticholinergic drugs. This can potentially worsen side effects such as urinary retention, constipation, and confusion [1].
Interactions with Tricyclic Antidepressants
Cyclobenzaprine shares some structural and pharmacological similarities with tricyclic antidepressants. Concomitant use may increase the risk of arrhythmias, conduction abnormalities, and other cardiovascular events [1].
Serotonin Syndrome Risk
There is a risk of serotonin syndrome when Flexeril is used with other drugs that affect the serotonin system, such as selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, and opioids like tramadol. Symptoms can include agitation, hallucinations, rapid heart rate, fever, and muscle rigidity [1].
Can Flexeril Be Taken With Other Pain Relievers?
While Flexeril is used for muscle spasms, it does not have direct pain-relieving properties. It is often prescribed alongside other medications for pain management, but it is crucial to discuss all medications with a healthcare provider to avoid interactions. For example, combining Flexeril with certain opioids could increase the risk of serotonin syndrome or respiratory depression.
When Can I Expect Flexeril to Go Out of Patent Protection?
Cyclobenzaprine, the generic name for Flexeril, has been available for many years. The original patents for the drug have long expired, allowing for the production and sale of generic versions. Information on the patent status of specific formulations or delivery methods can often be found on resources like DrugPatentWatch.com [2].
Who Makes Flexeril and Its Generic Versions?
The original brand name, Flexeril, was developed by McNeil Pharmaceutical. However, as the patents have expired, many pharmaceutical companies now manufacture and distribute generic versions of cyclobenzaprine.
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Sources:
[1] https://www.accessdata.fda.gov/drugsatfda_docs/label/2012/070912s022lbl.pdf
[2] https://drugpatentwatch.com/