Methocarbamol vs. tizanidine: Differences, similarities, and side effects

In this article:

• What is methocarbamol?
• What is tizanidine?
• Dosage and administration
• What is methocarbamol?
• Conditions treated
• Which is stronger?
• Insurance coverage and cost comparison
• Side effects
• Interactions
• Drug warnings

In this article

• What is methocarbamol?
• What is tizanidine?
• Dosage and administration
• What is methocarbamol?
• Conditions treated
• Which is stronger?
• Insurance coverage and cost comparison
• Side effects
• Interactions
• Drug warnings

Methocarbamol (generic Robaxin) and tizanidine (generic Zanaflex) are commonly prescribed muscle relaxants for treating muscle spasms, stiffness, and pain. While both medications aim to relieve muscle tension, they work differently and are appropriate for different muscle conditions. We’ll guide you through the differences and similarities between methocarbamol and tizanidine, including how they work in the body, the conditions they treat, side effects, and cost to provide you with a clear understanding of which medication may be best for your condition and the risks and benefits of each. 

What is methocarbamol?

Methocarbamol, the generic form of Robaxin, is a centrally acting muscle relaxant available as an oral tablet approved by the Food and Drug Administration (FDA) for short-term relief of acute muscle pain caused by sprains, strains, and other musculoskeletal conditions in people ages 16 and older. Methocarbamol works in the body by depressing the central nervous system (CNS), brain, and spinal cord to produce muscle-relaxing effects, although it doesn’t have a direct impact on the muscles themselves. Methocarbamol is also available as an injection to relieve muscle stiffness due to tetanus, but it’s usually not a first choice and doesn’t replace other tetanus treatment options.

What is tizanidine?

Tizanidine, the generic form of Zanaflex, belongs to the class of drugs called centrally acting alpha-2 adrenergic agonists. It is used to treat muscle spasms in people with neurological conditions such as multiple sclerosis, spinal cord injury, or brain injury. Tizanidine blocks nerve signals that cause muscle stiffness and spasms, which helps relax muscles. Tizanidine causes fewer side effects than other treatments; however, it’s not the best choice for new neck or back muscle pain. The FDA has only approved tizanidine to treat muscle stiffness (spasticity). 

Dosage and administration

Methocarbamol is available as oral tablets in 500 mg and 750 mg strengths. It is also available as an injection (100 mg/mL). Intended for short-term use, methocarbamol is prescribed in doses of 1,500 milligrams (mg) by mouth every six hours for two to three days and then 1,000 mg by mouth every six hours. The dosage may vary depending on the individual’s health condition and the severity of the muscle spasms. Methocarbamol comes in tablet form or as an injectable solution.

Tizanidine is available in 2 mg, 4 mg, 6 mg capsules, and 2 mg and 4 mg tablets. The starting dose is 2–4 mg, taken as needed, with about two to four hours between doses and no more than three doses in 24 hours. Depending on your needs, the dose can be gradually increased up to 36 mg daily. Tizanidine works quickly to provide relief, but food can affect how your body absorbs it.

Methocarbamol vs. tizanidine comparison chart
	Methocarbamol	Tizanidine
Drug class	Centrally acting muscle relaxant, antispasmodic agent	Centrally acting skeletal muscle relaxant, alpha-2 adrenergic receptor agonist
Brand/generic status	Methocarbamol is the generic name; Robaxin is the brand name	Tizanidine is the generic name; Zanaflex is the brand name
What form(s) does the drug come in?	Tablet and injection	Tablet and capsules
What is the standard dosage?	Initial dose of 1,500 mg by mouth every 6 hours for 2–3 days and then 1,000 mg by mouth every 6 hours	The initial dose is 2 mg, followed by subsequent doses every 6–8 hours. Maximum of 3 doses in 24 hours
How long is the typical treatment?	Short-term	Short-term
Who typically uses the medication?	People 16 years and older	Adults 18 years and older

Methocarbamol vs. tizanidine: Conditions treated

Methocarbamol relieves muscle spasms caused by acute injuries such as strains, sprains, and musculoskeletal pain. It is also prescribed to treat lower back pain and other conditions involving muscle spasms resulting from injury or surgery. It’s not usually used for neurological conditions involving spasticity. Methocarbamol works best with non-medication treatments, such as rest and physical therapy. It may be prescribed off-label (non-FDA-approved uses) for fibromyalgia, tetanus, and migraine.

Tizanidine is primarily used to treat spasticity caused by neurological conditions such as multiple sclerosis, cerebral palsy, or spinal cord injury. It’s less commonly used for acute muscle spasms but is often chosen for long-term spasticity management. Tizanidine is a good option for patients who need ongoing muscle relaxation because of their chronic condition. It may be prescribed off-label for migraine and fibromyalgia. 

Compare methocarbamol vs. tizanidine conditions treated
Condition	Methocarbamol	Tizanidine
Muscle spasms	Yes	Yes
Musculoskeletal spasms	Yes	No
Tetanus	Off-label	No
Migraine	Off-label	Off-label
Fibromyalgia	Off-label	Off-label
Sprains	Yes	No
Spasticity	No	Yes

Methocarbamol vs. tizanidine: Which is stronger?

Methocarbamol and tizanidine are both effective drugs for treating muscle conditions. However, little recent data exists comparing muscle relaxants’ efficacy.

A 2022 meta-analysis examining the effectiveness of various medications for muscle pain found that the differences in how much each medicine, including methocarbamol and tizanidine, helped were not significant enough to determine that one was better than the others. The results were similar no matter the person’s age, sex, or symptoms at the start.

Another meta-analysis from 2004 assessed over 100 different trials comparing several muscle relaxants, including Lioresal (baclofen), Soma (carisoprodol), Robaxin (methocarbamol), Skelaxin (metaxalone), and Valium (diazepam). Overall, the study found that these drugs are comparable in efficacy and safety. Other guidelines suggest muscle relaxants cause increased drowsiness and should only be used short-term.

Tizanidine was shown to be effective for spasticity due to multiple sclerosis and for musculoskeletal conditions such as acute neck or back pain. The meta-analysis evaluated over 100 different trials comparing several muscle relaxants, including Robaxin (methocarbamol), Skelaxin (metaxalone), and Valium (diazepam). Overall, the study found that these drugs are comparable in efficacy and safety. 

It’s important to note that only a healthcare provider can determine the most effective medication for a patient. They can review an individual’s specific medical condition, medical history, and any medications they may already be taking to avoid potential drug interactions with methocarbamol or tizanidine. 

Methocarbamol vs. tizanidine: Insurance coverage and cost comparison

Methocarbamol is available in both brand-name (Robaxin) and generic forms. The average price of methocarbamol is $31 for 30, 500 mg tablets, but with a SingleCare prescription discount card, you can pay about $5.

Tizanidine is also available in generic and brand-name form (Zanaflex). Depending on the dosage and formulation, tizanidine costs slightly more than methocarbamol, at about $49 for 30, 4 mg tablets. However, with a SingleCare card, you can access coupons that lower the cost to about $3, depending on your choice of pharmacy.

Most insurance plans, including Medicare Part D, generally cover methocarbamol and tizanidine. However, costs can vary depending on dosage, quantity, and pharmacy.

Compare methocarbamol vs. tizanidine cost and coverage
	Methocarbamol	Tizanidine
Typically covered by insurance?	Yes	Yes
Typically covered by Medicare Part D?	Yes	Yes
Quantity	30, 500 mg tablets	30, 4 mg tablets
Average cost without insurance*	$31	$49
SingleCare cost*	$5 with coupon	$3 with coupon

*Drug prices fluctuate and vary by pharmacy. This was the cost at the time of publication.

Methocarbamol vs. tizanidine side effects

The most common side effects of methocarbamol are drowsiness, dizziness, lightheadedness, and nausea. Although generally well tolerated, it may cause blurred vision, headache, and skin rash. Serious side effects are rare but may include allergic reactions, seizures, leukopenia (low white blood cells), cholestatic jaundice (build-up of bile), or low blood pressure. Older adults tend to be at higher risk for side effects. It is not safe to take certain pain medications, such as opioid medications, with methocarbamol. Talk to a healthcare provider if you notice any signs or symptoms of possible serious side effects.

Tizanidine has a more sedative effect than methocarbamol. Common side effects include dry mouth, weakness, and low blood pressure (hypotension). Because of its CNS depressant effect, it may also cause bradycardia (slow heart rate) and sedation, especially when taken with other CNS depressants such as alcohol or benzodiazepines. Compared to methocarbamol, tizanidine is more likely to cause drowsiness, sleepiness, and fatigue. 

Each person’s medical history, current medication list, and overall health can influence how these drugs affect them. Consulting your healthcare professional ensures that the medication chosen is safe and effective based on their medical needs. Always follow professional guidance to avoid potential drug interactions or adverse effects.

Compare methocarbamol vs. tizanidine side effects
	Methocarbamol		Tizanidine
Side effect	Applicable?	Frequency	Applicable?	Frequency
Drowsiness	Yes	% not reported	Yes	48%
Dry mouth	No	% not reported	Yes	49%
Headache	Yes	% not reported	No	–
Fatigue	No	% not reported	Yes	41%
Dizziness	Yes	% not reported	Yes	16%
Nausea	Yes	% not reported	No	–
Constipation	No	% not reported	Yes	4%
UTI	No	% not reported	Yes	10%
Involuntary movements	No	% not reported	Yes	3%
Anaphylactic reaction	Yes	% not reported	No	% not reported
Blurred vision	Yes	% not reported	No	% not reported

This may not be a complete list of adverse effects that can occur. Please consult your healthcare provider to learn more. 

Source: DailyMed (Tizanidine), DailyMed (Methocarbamol)

Methocarbamol and tizanidine interactions

Methocarbamol and tizanidine interact with other medications, which is why it is important to let your healthcare provider know about other medications and supplements you may be taking. Both drugs can interact with other CNS depressants (like alcohol), increasing the risk of severe drowsiness or breathing problems. 

Methocarbamol interactions

While methocarbamol can be an effective treatment option for some people, there are interactions that are important to be aware of and avoid. 

Methocarbamol should not be used with alcohol, sedatives, or other drugs that slow down your brain (CNS depressants), as this can make you feel more drowsy and dizzy. It may also affect your ability to drive or use machines safely. Do not drive or operate machinery until you are sure that methocarbamol does not affect your alertness and reaction time. 

Methocarbamol may also interact with drugs that affect liver enzymes, such as warfarin and certain anticonvulsants. If your healthcare provider decides that the combination of interacting medications is necessary due to your health condition, they may prescribe the lowest possible doses for the shortest time. 

Tizanidine interactions

Several drug interactions are associated with the use of tizanidine. Tizanidine is mainly broken down in the body by the CYP1A2 enzyme in the liver. Drugs that block this particular enzyme can increase tizanidine levels in the body. Tizanidine should not be taken with certain drugs like CYP1A2 inhibitors (such as ciprofloxacin or fluvoxamine), as this can lead to dangerously low blood pressure, slow heart rate, or extreme drowsiness. It’s also not recommended to consume alcohol, oral contraceptives, or other CNS depressants with tizanidine. 

Do not use methocarbamol or tizanidine if you are allergic to either of them. Other drug interactions may occur, as this is not a complete list. Consult your healthcare provider or pharmacist for a full list of drug interactions. 

Compare methocarbamol vs. tizanidine drug interactions
Drug	Drug class	Methocarbamol	Tizanidine
Ciprofloxacin Cimetidine Fluvoxamine Acyclovir Ticlopidine	CYP1A2 inhibitors	No	Yes
Ethinyl estradiol Norethindrone Levonorgestrel	Oral contraceptives	No	Yes
Phenobarbital Pentobarbital Secobarbital	Barbiturates	Yes	Yes
Oxycodone Hydrocodone Tramadol	Opioids	Yes	Yes
Alprazolam Lorazepam Diazepam	Benzodiazepines	Yes	Yes
Alcohol	Alcohol	Yes	Yes
Amitriptyline Desipramine Imipramine Nortriptyline	Tricyclic antidepressants	Yes	No
Desvenlafaxine Duloxetine Venlafaxine	SSRI antidepressants	Yes	No
Citalopram Escitalopram Fluoxetine Fluvoxamine Paroxetine Sertraline	SNRI antidepressants	Yes	No
Cetirizine Diphenhydramine	Antihistamines	Yes	No
Eszopiclone Zaleplon Zolpidem	Sedative hypnotics	Yes	No

Methocarbamol and tizanidine drug warnings

Methocarbamol is not a controlled substance and is not considered habit-forming, but it can cause drowsiness, dizziness, and coordination problems. Be cautious when doing activities that require alertness, like driving. There’s not enough research to confirm whether methocarbamol is safe during pregnancy or while breastfeeding, so talk to your healthcare provider before using it.

Tizanidine can harm your liver and kidneys, so your healthcare provider might need to monitor your liver function regularly. Stopping it suddenly, especially after long-term use, can lead to withdrawal symptoms and a sudden increase in blood pressure, which can raise the risk of stroke. It is not recommended during pregnancy or while breastfeeding because it can pass into breast milk, and its safety is uncertain. If you have liver or kidney issues, tizanidine might not be the right medication for you.

Always check with your healthcare provider before starting or stopping either medication.

Bottom line

Methocarbamol and tizanidine are effective for treating muscle problems, but they work differently. Choosing the right one depends on your condition, how long you need treatment, and the possible side effects and drug interactions.

Methocarbamol may be better for short-term relief of muscle spasms from injuries. Tizanidine might be a better fit for long-term treatment of muscle stiffness caused by chronic conditions like multiple sclerosis.

Always talk to your healthcare provider to decide which medicine is best for your needs, and remember to consider any side effects or interactions with other drugs you’re taking.