Why is cyclobenzaprine a high risk medication?

Cyclobenzaprine isn't generally considered a high-risk medication when taken as prescribed. But it does carry some risks that require consideration and monitoring. For instance, cyclobenzaprine can cause or contribute to serotonin syndrome, a condition caused by too much of the chemical serotonin in the brain. It doesn’t usually develop from cyclobenzaprine alone; the drug itself has a small effect on serotonin. But taking cyclobenzaprine with other medications that affect serotonin can raise the risk of serotonin syndrome. Other risks are also possible. View original source