- Side Effects
- Drug Interactions
- Pregnancy & Breastfeeding
- What Else to Know
Generic Name: cyclobenzaprine
Brand Names: Flexeril, Amrix, Fexmid
Drug Class: Skeletal Muscle Relaxants
What is cyclobenzaprine, and what is it used for?
Cyclobenzaprine is a muscle relaxant. Cyclobenzaprine relieves muscle spasms when the spasm is due to local problems, that is, in the muscle itself and not in the nerves controlling the muscles. Cyclobenzaprine has no effect on muscle function. Cyclobenzaprine seems to accomplish its beneficial effect through a complex mechanism within the nervous system, probably in the brainstem.
Cyclobenzaprine is used with rest and physical therapy for short-term relief of muscle spasms associated with acute painful muscle and skeletal conditions. It is only for short-term use, up to two or three weeks.
What are the side effects of cyclobenzaprine?
The most common side effects of cyclobenzaprine include:
Other reported side effects include:
- Blurred vision,
- Unpleasant taste
- Acid reflux
- Abdominal pain or discomfort
Possible serious side effects include:
- Abnormal heart beats
- Heart attacks
- Heat stroke
Abrupt cessation after prolonged therapy may cause withdrawal symptoms such as headaches, nausea, and weakness.
What is the dosage for cyclobenzaprine?
- The recommended dose of cyclobenzaprine dose is 5 or 10 mg three times daily using immediate release tablets or 15 or 30 mg once daily using extended release tablets.
Which drugs interact with cyclobenzaprine?
- Cyclobenzaprine is chemically related to the tricyclic class of antidepressants, for example, amitriptyline (Elavil, Endep), nortriptyline Pamelor). As such, it should not be taken with or within two weeks of any monoamine oxidase (MAO) inhibitor, for example, isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and procarbazine (Matulane). High fever, convulsions, and even death can occur when these drugs are used together.
- Cyclobenzaprine interacts with other medications and drugs that slow the brain's processes, such as
- benzodiazepines, for example, diazepam (Valium), lorazepam (Ativan), and
Pregnancy and breastfeeding
- There are no adequate studies of cyclobenzaprine in pregnant women. However, studies in animals suggest no important effects on the fetus. Cyclobenzaprine therefore can be used in pregnancy if the physician feels that it is necessary.
- It is not known whether cyclobenzaprine is secreted in milk. However, since it is related to the tricyclic antidepressants, some of which are excreted in breast milk, caution is advised in using this medication in women who are breastfeeding.
What else should I know about cyclobenzaprine?
- Is available in generic form. You need a prescription for this drug.
- Is available as Tablets: 5 and 10 mg. and Capsules (Extended Release): 15 and 30 mg.
- Tablets should be stored between 15 C and 30 C (59 F and 86 F).
- Was approved by the FDA in August 1977
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Cyclobenzaprine is a drug prescribed for the short-term relief of muscle spasms associated with acute painful muscle and skeletal conditions. Cyclobenzaprine is used with rest and physical therapy for short-term relief of muscle spasms associated with acute painful muscle and skeletal conditions. It is only for short-term use, up to two or three weeks. Common side effects include dry mouth, fatigue, and headaches. Possible serious side effects include stroke, heart attacks, and heat stroke. Consult your doctor if pregnant or breastfeeding.
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Related Disease Conditions
Muscle spasms are involuntary muscle contractions that come on suddenly and are usually quite painful. Dehydration, doing strenuous exercise in a hot environment, prolonged muscle use, and certain diseases of the nervous system may cause muscle spasms. Symptoms and signs of a muscle spasm include an acute onset of pain and a possible bulge seen or felt beneath the skin where the muscle is located. Gently stretching the muscle usually resolves a muscle spasm.
Acute injuries, medical conditions, and chronic use conditions are causes of knee pain. Symptoms and signs that accompany knee pain include redness, swelling, difficulty walking, and locking of the knee. To diagnose knee pain, a physician will perform a physical exam and also may order X-rays, arthrocentesis, blood tests, or a CT scan or MRI. Treatment of knee pain depends upon the cause of the pain.
Lower Back Pain (Lumbar Spine Pain)
There are many causes of back pain. Pain in the low back can relate to the bony lumbar spine, discs between the vertebrae, ligaments around the spine and discs, spinal cord and nerves, muscles of the low back, internal organs of the pelvis, and abdomen, and the skin covering the lumbar area.
Sciatica pain, caused by irritation of the sciatic nerve, typically radiates from the low back to behind the thigh to below the knee. Disc herniation is usually the cause of sciatica. Medication to alleviate pain, physical therapy, and bed rest are treatments for sciatica.
Shoulder and Neck Pain
Shoulder and neck pain may be caused by bursitis, a pinched nerve, whiplash, tendinitis, a herniated disc, or a rotator cuff injury. Symptoms also include weakness, numbness, coolness, color changes, swelling, and deformity. Treatment at home may incorporate resting, icing, and elevating the injury. A doctor may prescribe pain medications and immobilize the injury.
Foot pain may be caused by injuries (sprains, strains, bruises, and fractures), diseases (diabetes, Hansen disease, and gout), viruses, fungi, and bacteria (plantar warts and athlete's foot), or even ingrown toenails. Pain and tenderness may be accompanied by joint looseness, swelling, weakness, discoloration, and loss of function. Minor foot pain can usually be treated with rest, ice, compression, and elevation and OTC medications such as acetaminophen and ibuprofen. Severe pain should be treated by a medical professional.
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Ankle Pain (Tendonitis)
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Neck Pain (Cervical Pain)
Neck pain (cervical pain, cervicalgia) may be caused by any number of disorders and diseases. Tenderness is another symptom of neck pain. Though treatment for neck pain really depends upon the cause, treatment typically may involve heat/ice application, traction, physical therapy, cortisone injection, topical anesthetic creams, and muscle relaxants.
Arthritis, bursitis, IT band syndrome, fracture, and strain are just some of the causes of hip pain. Associated symptoms and signs include swelling, tenderness, difficulty sleeping on the hip, and loss of range of motion of the hip. Treatment depends upon the cause of the hip pain but may include anti-inflammatory medications and icing and resting the hip joint.
Elbow pain is most often the result of tendinitis, which can affect the inner or outer elbow. Treatment includes ice, rest, and medication for inflammation. Inflammation, redness, warmth, swelling, tenderness, and decreased range of motion are other symptoms associated with elbow pain. Treatment for elbow pain depends upon the nature of the patient's underlying disease or condition.
A herniated disc may be caused by injury or degeneration from age. Symptoms depend on the location of the herniation and whether nerve tissue is being irritated. An MRI or CT scan is performed to diagnose a herniated disc. Treatment may involve physical therapy, cortisone injection, pain medications, anti-inflammatory medications, muscle relaxants, and surgery.
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