What Are Muscle Relaxants For Pain Management?Chronic pain, such as chronic musculoskeletal pain, can lead to many potential challenges for physicians in terms of diagnosis, treatment, and long-term outcomes.
Some estimates have suggested that over $100 billion is spent annually within the United States alone on the management of chronic pain.
Patients suffering from musculoskeletal pain frequently complain of symptoms of pain and discomfort within the muscles, bones, nerves, ligaments, and tendons of the body.
Symptoms may emerge rapidly and worsen in severity rather quickly (i.e., acute onset) or they may emerge more slowly and have a more long-lasting course (i.e., chronic). Musculoskeletal pain that has persisted for three months or more is regarded as chronic in nature.
Chronic musculoskeletal pain can be either widespread or localized to one particular area. One of the most common forms of chronic musculoskeletal pain is lower back pain.
Other common forms of chronic musculoskeletal pain can include myalgia (i.e., muscle pain), stress fractures, and tendinitis. Patients experiencing muscle spasms or muscle spasticity often also complain of concurrent musculoskeletal pain.
The underlying cause for chronic musculoskeletal pain can be widely varied. In fact, chronic musculoskeletal pain can be caused by injury to any of the underlying structures, including nerves, joints, bones, muscles, ligaments, or tendons.
Chronic musculoskeletal pain can also be the result of overuse, poor posture, prolonged immobilization, or even degenerative conditions.
In terms of chronic musculoskeletal pain, in particular, oral analgesics, such as non-steroidal anti-inflammatory drugs (NSAIDs), may provide patients with only minimal relief from debilitating symptoms of pain and discomfort. Muscle relaxants, which are also known as skeletal muscle relaxants, are a type of medication that can be used to effectively treat symptoms of pain and discomfort associated with musculoskeletal conditions. Muscle relaxants do not actually act on the muscles themselves. Instead, these drugs affect change through their impact on the central and peripheral nervous system. More specifically, these drugs cause the muscles of the body, along with other structures, to relax. This is believed to be the primary method by which these drugs have their analgesic effects.
Types Of Muscle Relaxants For Pain ManagementThere are a wide variety of muscle relaxants available. Some of the most commonly prescribed muscle relaxants are discussed below.
Baclofen is a type of muscle relaxant that acts on the central nervous system. This medication is typically prescribed for the treatment of muscle spasticity that commonly occurs as the result of multiple sclerosis, as well as spinal cord injuries. Many physicians prefer baclofen due to the fact that there is very little evidence suggesting that it causes liver injury. Possible side effects associated with taking baclofen include: mood changes, nausea, drowsiness, fatigue, vision disturbances, dizziness, weakness, headache, light-headedness, dry mouth, muscle aches, difficulty breathing, confusion, insomnia, nightmares, increased urges to urinate, unsteadiness, increased sweating, skin rash, or shakiness.
Carisoprodol is another type of muscle relaxant that acts on the central nervous system. This medication is typically prescribed for the treatment of acute pain associated with a number of disorders of the musculoskeletal system. This medication has not been associated with any significant hepatic injury. Common side effects associated with taking carisoprodol include: headache, drowsiness, or dizziness.
Chlorzoxazone is another type of muscle relaxant that acts on the central nervous system. This medication is typically prescribed for the treatment of low back pain, as well as muscle spasms. Previous studies examining the effectiveness of chlorzoxazone have yielded mixed results. Further, there have been some reports of chlorzoxazone use being associated with acute liver injury, though these reports are rare. Common side effects associated with taking chlorzoxazone include: tremor, headache, fatigue, dizziness, or drowsiness.
Cyclobenzaprine is a type of muscle relaxant that also falls into the class of tricyclic antidepressant medications.
This medication is typically used to treat symptoms of painful muscle spasms associated with a variety of acute muscle conditions.
Despite its relation to tricyclic antidepressant medications, cyclobenzaprine is not associated with any significant liver damage.
Common side effects associated with taking cyclobenzaprine include: dizziness, headache, sleepiness, and dry mouth.
Dantrolene is a type of muscle relaxant that acts on the peripheral nervous system rather than the central nervous system. This medication is generally used to treat symptoms of chronic spasticity. Dantrolene is also used to as a prophylaxis against and the treatment for malignant hyperthermia. Dantrolene has been associated with causing acute liver damage, which can be quite severe and may even be fatal. Possible side effects associated with taking dantrolene include: fatigue, dizziness, drowsiness, diarrhea, general feelings of unwell, nausea, vomiting, abdominal pain, loss of appetite, headache, acne, rash, disturbances in vision or speech, chills, fever, seizures, difficulty breathing, fever, fluid in the lungs, or swelling in the tissue surrounding the heart.
Metaxalone is another type of muscle relaxant that acts on the central nervous system. This medication is used to treat symptoms of acute pain associated with various musculoskeletal conditions, as well as painful symptoms of muscle spasms. Using metaxalone has not been associated with significant hepatic injury or elevations in serum aminotransferase levels. While side effects are not common when taking metaxalone, some possible side effects include: headache, dry mouth, nausea, drowsiness, or dizziness.
Methocarbamol is another type of muscle relaxant that acts on the central nervous system. This medication is used to treat symptoms of acute pain associated with various musculoskeletal conditions. Using methocarbamol has not been associated with significant liver damage. Common side effects associated with taking methocarbamol include: nausea, skin rash, blurred vision, or headache.
Orphenadrine is another type of muscle relaxant that acts on the central nervous system. This medication is used to treat the acute symptoms of many painful musculoskeletal conditions. Using orphenadrine has not been associated with significant liver damage or clinically-relevant symptoms of liver disease. The most common side effects associated with taking orphenadrine include: flushing, dry mouth, drowsiness, diaphoresis, disturbances in vision, or confusion.
Tizanidine is another type of muscle relaxant that acts on the central nervous system. This medication is used to treat the acute symptoms of muscle spasms, as well as chronic muscle spasticity. The use of tizanidine has been associated with acute liver damage, which can be quite severe and may even be fatal. The most common side effects associated with taking tizanidine include: dry mouth, dizziness, drowsiness, fatigue, muscular weakness, and in some instances hypotension.
Conditions Related To Muscle Relaxants For Pain ManagementMuscle relaxants can be used to treat a variety of musculoskeletal conditions resulting in symptoms of pain and discomfort.
Some of the more commonly reported symptoms that have been effectively treated with muscle relaxants include:
- Bone pain: Bone pain is most typically described as dull, deep, and penetrating. This type of pain is most commonly the result of an injury, such as a bone fracture.
- Connective tissue pain: Pain that arises within the tendons or ligaments of the body is usually described as pain or discomfort that worsens when the affected area is moved or stretched. This type of pain is most commonly the result of an injury, such as a strain or sprain.
- Muscle pain: Muscle pain is most typically described as less intense than that of bone pain, though it can still be severe. In many instances, muscle pain is the result of an injury, loss of blood flow to the muscle tissue, infection, autoimmune reaction, or tumor. Muscle pain can also arise as the result of muscle strains or sprains.
- Tunnel syndromes: Tunnel syndromes refer to various musculoskeletal conditions that are the result of nerve compression, including cubital tunnel syndrome, tarsal tunnel syndrome, and carpal tunnel syndrome. This type of pain is typically described as a painful burning sensation and can feel as though it runs along the nerve.
- Joint pain: Joint pain is often described as an aching within the joint. Patients with joint pain may also report symptoms of joint stiffness and joint swelling. In most instances, arthritis is the root of the symptoms of joint pain.
- Fibromyalgia: Fibromyalgia is a condition that leads to symptoms of pain within the ligaments, tendons, and muscles of the body. It is not uncommon for patients to have difficulty describing their symptoms of fibromyalgia pain.
ConclusionMusculoskeletal pain is a commonly occurring pain condition among adults in the United States.
Patients suffering from symptoms of chronic musculoskeletal pain may not achieve relief from symptoms with traditional oral analgesics, such as non-steroidal anti-inflammatory drugs (NSAIDS).
As such, it may be necessary for these patients to be prescribed muscle relaxants for the treatment of their symptoms.
Patients are encouraged to speak with their doctor about the risks and benefits associated with muscle relaxants for managing their symptoms of pain.
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