Robaxin vs Soma

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For patients with muscular pain or discomfort, certain medications that target the central nervous system can help in easing muscle spasms and managing symptoms. Robaxin and Soma are two such drugs that are prescribed for this purpose. They both work by affecting the communication among nerves in parts of the brain that control pain sensations and muscle relaxation.

Robaxin, also known as methocarbamol, is a centrally acting muscle relaxant often used to treat skeletal muscle spasms. On the other hand, Soma (carisoprodol) is another type of centrally acting skeletal muscle relaxant but it's metabolized into meprobamate which has anxiolytic and sedative properties contributing to its overall effect.

Although both drugs serve similar purposes, their pharmacological profiles differ slightly which may affect a patient's choice between them depending on individual factors like tolerance for potential side effects or interaction with other medicines.

What is Robaxin?

Methocarbamol (the generic name for Robaxin) was one of the first muscle relaxant medications to be developed, marking a significant advancement over previous treatments. Methocarbamol was approved by the FDA in 1957. Robaxin works by blocking nerve impulses or pain sensations that are sent to your brain, effectively "trapping" these signals and preventing them from causing discomfort. It is primarily prescribed for relieving muscle pain and spasms due to strains or injuries. Robaxin has a selective influence on the nervous system with only minor effects on other physiological functions which results in it having fewer side effects than other muscle relaxants like Carisoprodol (Soma), which have stronger effects on overall body systems.

What conditions is Robaxin approved to treat?

Robaxin is FDA-approved for the treatment of various muscle-related conditions, including:

  • Muscular pain and spasms
  • Muscle injuries, particularly those involving sprains or strains
  • As an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute, painful musculoskeletal conditions.

On the other hand, Soma (Carisoprodol) is also approved for similar applications but specifically:

  • Short-term treatment of skeletal muscle conditions that are accompanied by severe pain.

How does Robaxin help with these illnesses?

Robaxin, also known as methocarbamol, works to relieve muscle spasms and pain by blocking nerve impulses (or pain sensations) that are sent to your brain. It is a central nervous system depressant that provides relief from muscular tension or spasms resulting from a range of conditions, including injuries and physical stress.

Soma, on the other hand, which contains carisoprodol, operates in a similar manner but its exact mechanism of action isn't fully understood. It's believed to alter interneuronal activity in the spinal cord and descending reticular formation within the brain - areas linked with pain perception.

Both drugs work by affecting communication between nerves in parts of the body where muscle relaxants have their desired effect. The main difference lies in their strength and side effects; Soma is usually considered stronger than Robaxin but may come with more potential for side effects like drowsiness or dependence.

What is Soma?

Soma, also known by its generic name Carisoprodol, is a muscle relaxer that works by blocking pain sensations between the nerves and the brain. It was first approved by the FDA in 1959. Soma is typically used along with rest and physical therapy to treat skeletal muscle conditions such as pain or injury.

Unlike Robaxin (methocarbamol), which can cause more drowsiness and sedation due to its action on your central nervous system, Soma has less of these side effects. Its specific mechanism in relieving discomfort from acute painful musculoskeletal conditions makes it beneficial for patients who require short-term relief from muscle spasticity without excessive sedation.

Moreover, while both drugs have potential for abuse and dependency when used long term or at high doses, Soma may be generally better tolerated. However, like all medications, Soma should only be taken under guidance from a healthcare professional.

What conditions is Soma approved to treat?

Soma, also known as carisoprodol, is approved by the FDA for the treatment of conditions such as:

  • Discomfort related to acute, painful musculoskeletal conditions
  • Spasms related to muscle injuries or strains

It's important to note that Soma should only be used for short-term treatment (up to two or three weeks), and its effectiveness beyond this timeframe has not been verified.

How does Soma help with these illnesses?

Soma, also known as carisoprodol, is a muscle relaxant that works by blocking pain sensations between the nerves and the brain. It's commonly prescribed to treat skeletal muscle conditions such as pain or injury in combination with rest and physical therapy. Soma alters interneuronal activity in the spinal cord and descending reticular formation in the brain, resulting in its sedative properties and relief from discomfort associated with acute painful musculoskeletal conditions. This action differs somewhat from Robaxin (methocarbamol), another muscle relaxant that primarily works on the central nervous system to produce its muscle relaxant effects, rather than directly on skeletal muscles. Although both drugs serve similar purposes, patients who don't respond well to one might find better results with the other due their different mechanisms of action.

How effective are both Robaxin and Soma?

Both methocarbamol (Robaxin) and carisoprodol (Soma) have established histories of success in treating patients with muscle spasms, and they were initially approved by the FDA only a few years apart. Since they act on different biochemical pathways to achieve muscle relaxation, they may be prescribed under different circumstances. The effectiveness of Robaxin and Soma in alleviating muscular pain was directly studied in several clinical trials; both drugs exhibited similar efficacy in managing symptoms as well as similar safety profiles.

A 2004 review of meta-analysis reports on Robaxin demonstrated that it is effective at relieving musculoskeletal pain following injury or during physical therapy sessions. Its side effect profile is generally favorable over many other muscle relaxants, with common side effects including dizziness and lightheadedness which are usually transient. Additionally, it has been shown to be well-tolerated even in elderly populations due to its low potential for causing confusion or sedation.

A 2016 review indicated that Soma seems more effective than placebo at treating acute back or neck pain associated with muscle spasms and tension. However, due to its potential for abuse and dependence when used long-term, Soma is typically considered only after non-drug therapies or other first-line treatments have failed. Data confirming its efficacy as a stand-alone treatment are less robust than those for Robaxin due to these concerns about misuse. Nonetheless, because it blocks interneuronal activity within the descending reticular formation and spinal cord - leading to sedation at higher doses - Soma may serve an important function for patients who do not respond well to other treatments.

abstract image of a researcher studying a bottle of drug.

At what dose is Robaxin typically prescribed?

Oral dosages of Robaxin range from 1500-7500 mg/day in divided doses, but studies have shown that for most adults, an initial dosage of 1500 mg four times a day is usually sufficient for treating muscle spasms. The dosage can be adjusted depending on the severity and duration of symptoms. For Soma, the usual adult dosage is 250-350 mg taken three times a day and at bedtime. It should only be used for short periods (up to two or three weeks) as there's inadequate evidence of effectiveness for more prolonged use. In either case, it's crucial not to exceed the maximum recommended dose unless directed by your healthcare provider.

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At what dose is Soma typically prescribed?

Soma therapy typically begins at a dose of 250-350 mg three times a day and at bedtime. The dosage can be adjusted according to the severity of the disorder, but should not exceed 1400 mg/day. These doses are usually spaced about five to six hours apart throughout the day and before sleeping. If there is no adequate response to treatment after two to three weeks, your healthcare provider might consider increasing your dosage or switching you onto another medication depending on your pain levels and overall health condition.

What are the most common side effects for Robaxin?

Common side effects of Robaxin include:

  • Drowsiness or dizziness
  • Upset stomach, nausea, and vomiting
  • Fever and flushing (warmth, redness, or tingly feeling)
  • Constipation or diarrhea
  • Blurred vision
  • Insomnia (trouble sleeping)
  • Memory problems or forgetfulness

On the other hand, Soma can cause:

  • Drowsiness
  • Dizziness
  • Headache
  • Rapid heart rate (tachycardia) -Nausea, vomiting

These are not all the possible side-effects. If any of these symptoms persist or worsen over time consult with a healthcare provider immediately. It is important to take these medications exactly as prescribed by your healthcare provider to minimize potential risks and adverse effects.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Robaxin?

While Robaxin is generally well tolerated, in some rare instances it can lead to serious adverse reactions. These may include:

  • Allergic reactions: hives; difficulty breathing; swelling of your face, lips, tongue, or throat
  • Seizures (convulsions)
  • Jaundice – yellowing of the skin and eyes due to liver damage
  • Slow heart rate
  • Lightheadedness that causes fainting
  • Signs of an overdose such as extreme drowsiness or loss of consciousness

In addition to this, there are also common side effects which although not life threatening should be reported to a healthcare provider. These include:

  • Dizziness or spinning sensation (vertigo)
  • Drowsiness
  • Upset stomach including nausea and vomiting.

Remember that while these side effects might seem daunting they only occur in a very small percentage of patients taking this medication. Always consult with your doctor if you feel any discomfort when taking Robaxin.

What are the most common side effects for Soma?

Commonly reported side effects of Soma (Carisoprodol) can include:

  • Drowsiness or sedation, which may disrupt normal sleep patterns
  • Headaches and dizziness that could affect balance and coordination
  • An increase in heart rate, leading to potential feelings of anxiety or nervousness
  • Digestive issues such as nausea, stomach discomfort, constipation and loss of appetite
  • Occasional blurred vision or eye disturbance
  • Potential for skin rash or other allergic reactions
  • Dry mouth causing sore throat and thirst
  • Less commonly, users might experience tremors, agitation/confusion that can lead to hostility. In certain cases there might be a slight weight loss effect.

Are there any potential serious side effects for Soma?

Soma, while an effective muscle relaxant for many people, can produce worrisome side effects in some cases. These include:

  • Signs of allergic reaction such as hives or itching; difficulty breathing; swelling in your face, lips, tongue or throat
  • Feelings of agitation or confusion
  • Depressed mood and increased feelings of sadness or thoughts about self harm
  • Seizures (convulsions)
  • Vision problems including blurred vision and seeing halos around lights
  • Rapid heart rate or irregular heartbeats
  • Unusual behavior changes marked by extreme excitement, irritation or restlessness Insomnia characterized by severe trouble sleeping.

If any of these symptoms are noticed after taking Soma it is crucial to seek immediate medical attention.

Contraindications for Robaxin and Soma?

Both Robaxin and Soma, like most muscle relaxants, may exacerbate symptoms of sleepiness or dizziness in some individuals. If you notice an increase in these side effects or any severe reactions such as trouble breathing, swelling of your face/tongue/throat, or a severe rash, please seek immediate medical attention.

Neither Robaxin nor Soma should be taken if you are taking medication for certain mental disorders (such as MAO inhibitors). Always inform your physician about all the medications you are currently using; drugs like MAO inhibitors will require a period of about 2 weeks to clear from your system before starting muscle relaxant therapy to prevent dangerous interactions with both Robaxin and Soma.

How much do Robaxin and Soma cost?

For the brand name versions of these drugs:

  • The price for 100 tablets of Robaxin (500 mg) averages around $130 which works out to approximately $1.30–$2.60/day, depending on your dose.
  • The cost for 90 tablets of Soma (350 mg) averages about $360, working out to roughly $4/day.

Thus, if you are in the higher dosage range for Robaxin (i.e., 1500 mg/day or higher), then brand-name Soma is likely more expensive on a per-day treatment basis. Please note that cost should not be a primary consideration in determining which of these drugs is right for you.

For the generic versions of Robaxin (methocarbamol) and Soma (carisoprodol), costs are significantly lower:

  • Methocarbamol is available in packs from 20 up to 500 tablets with approximate costs ranging from as low as $0.15 to $0.45 per day based on dosages between 500mg and up-to daily doses at therapeutic levels.
  • Carisoprodol comes in packs ranging from 30 up to around 180 pills with the cost per pill starting from about $.40/ day and going upwards depending upon quantity purchased and daily dosage requirements.

These prices can vary depending upon discounts applied by individual pharmacies or differences due to geographic location within the United States.

Popularity of Robaxin and Soma

Methocarbamol, in generic form as well as brand names such as Robaxin, was estimated to have been prescribed to about 3.2 million people in the US in 2020. Methocarbamol accounted for just over 6% of muscle relaxant prescriptions in the US. However, it appears to be one of the most common skeletal muscle relaxants used for musculoskeletal conditions or injury and has seen a steady increase since 2015.

Carisoprodol, including brand versions such as Soma, was prescribed to approximately 2.8 million individuals in the USA during the same year. In terms of total muscle relaxant prescriptions in the US, carisoprodol accounts for around 5%, but this figure is slowly decreasing due to its potential for abuse and dependency; thus its use is generally limited to short-term treatment periods of up to three weeks only.


Both Robaxin (methocarbamol) and Soma (carisoprodol) have been utilized for years in the management of acute musculoskeletal pain. They are backed by several clinical studies indicating their effectiveness at providing short-term relief from discomfort associated with painful muscle conditions. In some instances, these medications may be used together under careful supervision by a physician due to potential interactions.

Robaxin and Soma possess different modes of action; Robaxin is believed to work primarily on the central nervous system to achieve its muscle relaxant effects, while Soma interrupts neuronal communication within the reticular formation and spinal cord. Typically, choice between these two depends on individual patient factors such as severity of symptoms, general health condition, response to past treatment regimens or contraindications.

Both drugs are available in generic form which can lead to considerable cost savings for patients who must pay out-of-pocket expenses. The onset of relief provided by both Robaxin and Soma might not be immediate - an adjustment period could be required for noticeable effects.

Side-effect profiles are somewhat similar between these two medications; they're generally well-tolerated but users need to watch out for possible drowsiness or mild allergic reactions which occur less frequently. Unlike antidepressants like Prozac or Wellbutrin though, there's no evidence suggesting that users need monitor their moods when taking either drug. However, it is crucial that should any side-effects arise while using either medication - including unexpected mood swings - medical advice must be sought promptly.