Generic Name: cyclobenzaprine (sye kloe BEN za preen)Brand Names: Amrix, Comfort Pac with Cyclobenzaprine, Fexmid, Flexeril
Cyclobenzaprine is a muscle relaxant. It works by blocking nerve impulses (or pain sensations) that are sent to your brain.
Cyclobenzaprine is used together with rest and physical therapy to treat skeletal muscle conditions such as pain or injury.
Cyclobenzaprine may also be used for other purposes not listed in this medication guide.What is the most important information I should know about Amrix (cyclobenzaprine)?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.
a heart rhythm disorder;
congestive heart failure;
heart block; or
an overactive thyroid.
Before using cyclobenzaprine, tell your doctor if you are allergic to any drugs, or if you have:
problems with urination;
If you have any of these conditions, you may need a dose adjustment or special tests to safely take cyclobenzaprine.FDA pregnancy category B. This medication is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. It is not known whether cyclobenzaprine passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
Older adults may be more sensitive to the side effects of this medication.
Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.Take this medicine with a full glass of water. Do not crush, chew, break, or open an extended-release capsule. Swallow the pill whole. Breaking or opening the pill may cause too much of the drug to be released at one time.
Cyclobenzaprine is only part of a complete program of treatment that may also include rest, physical therapy, or other pain relief measures. Follow your doctor's instructions.Store cyclobenzaprine at room temperature away from moisture, heat, and light.
Overdose symptoms may include drowsiness, fast heartbeat, tremors or shaking, slurred speech, confusion, nausea, vomiting, hallucinations (seeing things), chest pain, or seizure (convulsions).
fast, pounding, or uneven heartbeats;
chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
sudden numbness or weakness, especially on one side of the body;
sudden headache, confusion, problems with vision, speech, or balance;
feeling light-headed, fainting;
confusion, weakness, lack of coordination;
nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
unusual thoughts or behavior, hallucinations (seeing things); or
easy bruising or bleeding, unusual weakness.
Less serious side effects may include:
dry mouth or throat;
drowsiness, dizziness, tired feeling;
loss of appetite, stomach pain, nausea;
diarrhea, constipation, gas; or
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.
Many drugs can interact with cyclobenzaprine. Below is just a partial list. Tell your doctor if you are using:
atropine (Donnatal, and others), benztropine (Cogentin), dimenhydrinate (Dramamine), methscopolamine (Pamine), or scopolamine (Transderm-Scop);
a bronchodilator such as ipratroprium (Atrovent) or tiotropium (Spiriva);
bladder or urinary medications such as darifenacin (Enablex), flavoxate (Urispas), oxybutynin (Ditropan, Oxytrol), tolterodine (Detrol), or solifenacin (Vesicare); or
irritable bowel medications such as dicyclomine (Bentyl), hyoscyamine (Anaspaz, Cystospaz, Levsin, and others), or propantheline (Pro-Banthine).
This list is not complete and there may be other drugs that can interact with cyclobenzaprine. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.