Do not take cyclobenzaprine if you have used an MAO inhibitor such as isocarboxazid (Marplan), tranylcypromine (Parnate), phenelzine (Nardil), or selegiline (Eldepryl, Emsam) within the past 14 days. Serious, life-threatening side effects can occur if you take cyclobenzaprine before the MAO inhibitor has cleared from your body.
You should not take cyclobenzaprine if you have recently had a heart attack, or if you have a heart rhythm disorder, congestive heart failure, heart block, or an overactive thyroid.
Cyclobenzaprine can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.
Avoid drinking alcohol, which can increase some of the side effects of cyclobenzaprine.