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What should I discuss with my doctor before taking cyclobenzaprine (Amrix, Comfort Pac with Cyclobenzaprine, Fexmid, Flexeril)?

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.

Do not use 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.

Before using cyclobenzaprine, tell your doctor if you are allergic to any drugs, or if you have:

• problems with urination;
• enlarged prostate;
• glaucoma; or
• liver disease.

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.

How should I take cyclobenzaprine (Amrix, Comfort Pac with Cyclobenzaprine, Fexmid, Flexeril)?

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.

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