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Virtually any disease as well as most injuries and surgical procedures involve some degree of pain. It's not surprising, then, that pain medications, also known as analgesics, are among the most commonly used drugs in the U.S. Pain can range from minor, acute complaints, such as a muscle sprain, to chronic, severe pain, such as that sometimes experienced by cancer patients. Some drugs used for other conditions also are effective at relieving certain types of pain. These drugs include certain drugs used for depression, epilepsy, and anxiety.
Pain medications can be broadly classified into two categories: prescription and nonprescription. In the latter category are several mild anti-inflammatory drugs (ibuprofen, naproxen), as well as acetaminophen. These are mainly meant for use with short-term, acute pain -- menstrual cramps,...
FLEXERIL
(cyclobenzaprine hydrochloride) Tablet, Film Coated
Cyclobenzaprine hydrochloride is a white, crystalline tricyclic amine salt with the empirical formula C20H21N•HCl and a molecular weight of 311.9. It has a melting point of 217#C, and a pKa of 8.47 at 25#C. It is freely soluble in water and alcohol, sparingly soluble in isopropanol, and insoluble in hydrocarbon solvents. If aqueous solutions are made alkaline, the free base separates. Cyclobenzaprine HCl is designated chemically as 3-(5H -dibenzo[a,d] cyclohepten-5-ylidene)-N, N-dimethyl-1-propanamine hydrochloride, and has the following structural formula:
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FLEXERIL 5 mg (Cyclobenzaprine HCl) is supplied as a 5 mg tablet for oral administration. FLEXERIL 10 mg (Cyclobenzaprine HCl) is supplied as a 10 mg tablet for oral administration.
FLEXERIL 5 mg (Cyclobenzaprine HCl) tablets contain the following inactive ingredients: hydroxypropyl cellulose, hypromellose, lactose, magnesium stearate, starch, titanium dioxide, Yellow D&C #10 Aluminum Lake HT, and Yellow FD&C #6 Aluminum Lake.
FLEXERIL 10 mg (Cyclobenzaprine HCl) tablets contain the following inactive ingredients: hydroxypropyl cellulose, hypromellose, iron oxide, lactose, magnesium stearate, starch, and titanium dioxide.
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Stop using cyclobenzaprine and call your doctor at once if you have any of these serious side effects:
Read All Potential Side Effects and See Pictures of Flexeril »
Before taking cyclobenzaprine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: overactive thyroid (hyperthyroidism), irregular heartbeats (arrhythmia), other heart problems (congestive heart failure, heart block or conduction disorders), recent heart attack, moderate or severe liver disease.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: severe difficulty urinating (urinary retention),...
Last reviewed on RxList: 4/13/2011
This monograph has been modified to include the generic and brand name in many instances.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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