Robaxin vs. Soma: Differences, similarities, and which is better for you

Drug overview & main differences | Conditions treated | Efficacy | Insurance coverage and cost comparison | Side effects | Drug interactions | Warnings | FAQ

Have you ever thrown out your back or had terrible back pain or spasms? Or have you ever turned the wrong way, which resulted in excruciating neck pain? If you’ve ever experienced any of these problems, your healthcare provider may have prescribed a muscle relaxant. Robaxin and Soma are two brand-name prescription drugs indicated for the treatment of muscle spasms. Both drugs are approved by the United States Food and Drug Administration (FDA).

Robaxin and Soma are classified in a group of medications called skeletal muscle relaxants. Robaxin and Soma are thought to work based on general CNS (central nervous system) depression and sedative properties. Also, Soma is metabolized to meprobamate, which is believed to relieve anxiety and cause sedation. However, it is unknown to what extent meprobamate helps relieve muscle spasms.

Because Soma may cause abuse or dependence, it is classified as a Schedule IV controlled substance. Although Robaxin and Soma are both muscle relaxants, they are not the same. Read on to learn more about Robaxin and Soma.

What are the main differences between Robaxin and Soma?

Robaxin (methocarbamol) and Soma (carisoprodol) are skeletal muscle relaxants. Robaxin is available in tablet and injection form. Soma is available in tablet form. Both medications can be used in adults. Soma should only be used for short periods, for a maximum of two to three weeks.

Conditions treated by Robaxin and Soma

Robaxin (What is Robaxin?) and Soma (What is Soma?) are indicated to relieve discomfort associated with acute, painful musculoskeletal conditions.

It is noted in the Robaxin prescribing information that Robaxin should be used along with rest, physical therapy, and other measures.

Soma’s prescribing information states that the medication should only be used for a maximum of two or three weeks.

Is Robaxin or Soma more effective?

There is not a lot of recent data comparing muscle relaxants for efficacy. A 2004 review of studies stated that there is “fair evidence” that Soma (carisoprodol), among others, is effective compared to placebo for acute back or neck pain, and “very limited or inconsistent data” on the efficacy of Robaxin (methocarbamol), among others. The researchers concluded that there is “insufficient evidence to determine the relative efficacy or safety” of either of these medications.

In fact, when considering a condition like low back pain, The American Pain Society and the American College of Physicians published guidelines recommending Tylenol (acetaminophen) or NSAIDs (nonsteroidal anti-inflammatory drugs like Advil) as first-line treatment for most patients. These medications are well-tolerated and have fewer side effects. Also, other measures can be tried, as recommended by your doctor, such as yoga, physical therapy, massage, and/or relaxation.

A 2014 review on skeletal muscle relaxants stated that if a first-line agent is not effective, then a muscle relaxant may be started. Muscle relaxants can be effective in treating muscle spasms but can have bothersome side effects. Also, as a controlled substance, Soma is associated with abuse and dependence. Because of this potential for abuse and dependence, patients with substance use disorder or a history of substance use disorder may do better with Robaxin, which is less likely to be abused.

Although muscle relaxants can be effective (compared to placebo) for short-term relief, there is a 50% risk of side effects. These side effects include headaches, blurred vision, and possible dependency. The study authors also note that there are no studies comparing muscle relaxants to first-line treatments like Tylenol or NSAIDs. Therefore, if a muscle relaxer is needed, individual factors should be considered, including symptoms, previous medications tried, potential side effects, and other medical conditions. Also, both drugs are on the Beers list of medications that may be inappropriate for adults over 65 years. They are poorly tolerated by older adults because of their side effects, sedation, and increased risk of falls and fractures.

The most effective medication can be determined by your healthcare provider, who can consider your symptoms, medical conditions, and medical history, along with any medicines you take that may interact with Robaxin or Soma.

Coverage and cost comparison of Robaxin vs. Soma

Robaxin and Soma are covered by most insurance and Medicare prescription plans in the generic form.

The out-of-pocket price of a standard generic Robaxin prescription (60, 750 mg tablets) is about $25. Using a free SingleCare card can lower the price to less than $15.

The out-of-pocket price of a generic Soma prescription (60, 350 mg tablets) is approximately $36. With a SingleCare coupon, you can purchase generic Soma for as low as $14.

Contact your insurance provider for up-to-date coverage information on Robaxin or Soma.

Get the SingleCare prescription discount card

Common side effects of Robaxin vs. Soma

Side effects of both Robaxin and Soma include drowsiness, dizziness, and headache. The Robaxin prescribing information does not report percentages of occurrence.

Robaxin’s other side effects may include nausea, vomiting, blurred vision, allergic reaction, confusion, seizures, and incoordination.

Other side effects of Soma can include flushing, tremor, agitation, irritability, nausea, vomiting, and seizures.

This is not a full list of side effects. Other, serious side effects can occur. Consult your healthcare provider for a complete list of adverse effects.

Source: DailyMed (Robaxin), DailyMed (Soma)

Drug interactions of Robaxin vs. Soma

Robaxin or Soma should not be combined with alcohol. Medications that cause central nervous system depression, such as opioids like Percocet, benzodiazepines like Valium, and antidepressants, should be avoided if possible when taking Robaxin or Soma. Additive effects can occur, both with CNS depression (causing profound sedation and impairment) and respiratory depression (causing slowed and/or difficulty breathing, and can be life-threatening). However, if the combination of interacting medications cannot be avoided, the lowest doses of each drug for the shortest duration of time should be used, and the patient should be closely monitored.

Other drug interactions may occur. Consult your healthcare provider for a full list of drug interactions. Tell your doctor about all of the medications you take, including prescription, over-the-counter, and vitamins.

Warnings of Robaxin and Soma

• Before using Robaxin or Soma, tell your healthcare provider about any medical conditions (such as liver or kidney problems) you have and all of the medications you take.
• Do not combine Robaxin or Soma with alcohol or medications that cause CNS depression (see additional information in the drug interaction section above).
• Robaxin or Soma may cause drowsiness or dizziness, which can impair your ability to drive or operate machinery. Do not drive or operate machinery until you are certain that Robaxin or Soma does not affect your alertness and reaction time.
• Do not use Robaxin or Soma if you are allergic to either component. Do not use Soma if you are allergic to meprobamate.
• Keep out of the reach of children and others.

Additional Soma warnings:

• Do not use Soma if you have a history of acute intermittent porphyria.
• Soma should only be used in adults ages 16 to 65 years old.
• As a controlled substance, Soma has been associated with abuse, dependence, withdrawal, misuse, and criminal diversion. Soma abuse can lead to overdose, which can cause low blood pressure, seizures, CNS and respiratory depression, and death. Your healthcare provider will assess the risk of abuse before prescribing Soma and limit the treatment length to a maximum of two to three weeks.
• In some cases, patients who took Soma had seizures. Most cases were related to multiple drug overdose.
• Stopping Soma abruptly can cause withdrawal symptoms, including insomnia, vomiting, headache, tremors, twitching, hallucinations, and psychosis. Ask your healthcare provider for medical advice on the best way to taper off Soma.
• Keep out of the reach of children and others, under lock and key if possible. Ask your pharmacist how to dispose of any remaining medication.
• An overdose of Soma can lead to CNS depression. Soma overdosages have led to death, coma, respiratory depression, low blood pressure, seizures, hallucinations, blurred vision, euphoria, incoordination, headaches, and delirium.
• Fatal overdoses of Soma have been reported. These overdoses have been accidental and non-accidental and have occurred alone or in combination with CNS depressants, even at the recommended dosage.

Frequently asked questions about Robaxin vs. Soma

What is Robaxin?

Robaxin is a skeletal muscle relaxant used to treat muscle spasms. It contains the ingredient methocarbamol.

What is Soma?

Soma is also used to treat muscle spasms. It is a muscle relaxer and contains carisoprodol.

Are Robaxin and Soma the same?

No. Both medications are known as muscle relaxants, but they have many differences, as outlined above. For example, they have different ingredients, dosages, and controlled substance classifications.

Is Robaxin or Soma better?

Your healthcare provider can determine if Robaxin or Soma is more appropriate for you, taking into account your symptoms and medical conditions, along with other medications you take that could potentially interact with Robaxin or Soma. Your doctor will also assess your risk for abuse or dependence if considering Soma.

Can I use Robaxin or Soma while pregnant?

Robaxin may cause fetal abnormalities and should not be used during pregnancy. Soma does not have enough data on use in pregnancy and is generally not used during pregnancy. Consult your healthcare provider for guidance on pregnancy or breastfeeding.

Can I use Robaxin or Soma with alcohol?

No. Avoid alcohol if you are taking Robaxin or Soma. Alcohol can cause additive effects with Robaxin or Soma and can cause CNS depression and impairment, and respiratory depression with slowed or difficult breathing, and could even cause a fatal overdose.

What muscle relaxer is the same as Soma?

Carisoprodol is the generic equivalent of Soma—Soma and carisoprodol are the same. Other muscle relaxers besides Robaxin and Soma you may have heard of include Flexeril (cyclobenzaprine), Skelaxin (metaxalone), and Zanaflex (tizanidine).

Is Robaxin an over-the-counter drug?

No. Robaxin is only available by prescription. Muscle relaxants are not available over-the-counter (OTC). Certain analgesics (pain relievers) like Tylenol (acetaminophen) or Advil (ibuprofen) are available OTC. Ask your healthcare provider if you should try an OTC medication before trying a muscle relaxant.

Is Robaxin a pain killer?

Robaxin is classified as a muscle relaxant. It can help with pain due to muscle spasms. It is not classified as a “pain killer,” but it does relieve pain and spasms.