Flexeril (cyclobenzaprine) is a muscle relaxant that is primarily used to treat muscle spasms, muscle stiffness, and pain in individuals who have musculoskeletal conditions. Its effectiveness is reduced for individuals who have central nervous system involvement (brain and spinal cord) that produces spasms, pain, or stiffness.
The drug is involved in increasing the release and availability of norepinephrine. Its medicinal use is limited for a short period of time, most often two weeks, due to the development of tolerance and the drug being ineffective after an individual has used it regularly. The drug is most commonly used in conjunction with other forms of treatment, particularly physical rehabilitation and other physical interventions. It is generally taken in capsule or tablet form and administered in small doses several times a day as opposed to one large dose. The common starting dose for the drug is 5 mg three times a day, which can be increased to 10 mg three times a day.
Overdose of Flexeril
Flexeril is not a significant drug of abuse according to data released by the Substance Abuse and Mental Health Services Administration (SAMHSA). The drug is very similar in its chemical structure to the tricyclic antidepressant drugs, and similar precautions and side effects occur with its use.
Abuse of Flexeril is believed to more commonly involve polydrug abuse. Flexeril abuse is not considered to be a primary issue, but combining Flexeril with other drugs to enhance their effects, such as alcohol, benzodiazepines, and narcotic pain medications like Vicodin, appears to be most the common form of abuse of Flexeril; however, its abuse is not widespread. In many situations, misuse of the drug may be unintentional, such as when elderly individuals take too much of it because they cannot remember how much they previously took.
Because Flexeril has central nervous system depressant effects, it does have the potential for overdose, although it appears that overdose on Flexeril alone is relatively rare. The overdose potential for Flexeril is a broader concern for elderly individuals who use the drug and for individuals who use the drug in conjunction with other central nervous system depressants. There are reports of fatalities as a result of Flexeril overdose.
Research reports indicate that the symptoms associated with Flexeril overdose include:
- Fast or irregular heartbeat
- Low blood pressure
- Potential cardiac arrest (rare)
- Slurred speech
- Nausea and/or vomiting
- Chest pains
- Tremors or shakiness
- Mental confusion
- Hallucinations and/or delusions
- Potential seizures
- Unconsciousness or coma
According to the above studies and the Food and Drug Administration (FDA), there is a rare potential for the development of a severe syndrome known as neuroleptic malignant syndrome as a result of an overdose on Flexeril. The symptoms associated with this syndrome include:
- High fever
- Significant alterations in blood pressure
- Accelerated heart rate
- Profuse sweating
- Rigid muscles
- Kidney failure
- Breakdown of muscle tissue into the bloodstream
This syndrome can be fatal if left unchecked.
When an individual uses Flexeril in conjunction with some other central nervous system depressant, the potential for overdose is increased because combining drugs that have similar effects enhances the effects of both drugs. This means that a smaller amount of either drug can result in an overdose.
In addition, the combined effects of withdrawal from drugs used in conjunction with each other can be much more intense than the effects of large doses of either drug alone. A 2011 study comparing the effects of an overdose of Flexeril to an overdose of a tricyclic antidepressant found that the most common effects associated with Flexeril overdose were drowsiness, accelerated or irregular heartbeat, and high blood pressure.
In the sample of 209 individuals who were suspected to have overdosed on Flexeril, there were no fatalities. Nonetheless, as mentioned above, there are recorded fatalities as a result of Flexeril overdose, and an overdose can be serious due to the drug’s central nervous system depressant effects. Potential issues with damage to the brain as a result of cardiac arrest and oxygen deprivation are serious potential complications of an overdose of Flexeril.