Methocarbamol
1 medicine
Methocarbamol is a sedating muscle relaxant used short-term for acute muscle spasm. Combining it with alcohol or other sedating drugs multiplies the drowsiness and can dangerously slow breathing.
Key facts
- Methocarbamol (sold as Robaxin) is a centrally acting muscle relaxant used short-term for acute, painful muscle spasm.
- It is taken several times a day, usually for no more than 2 to 3 weeks, alongside rest and physical therapy.
- It is sedating: combining it with alcohol, opioids, benzodiazepines or other sedating drugs multiplies the drowsiness and can dangerously slow breathing.
- Seek urgent care for a fast or irregular heartbeat, severe confusion, or signs of an allergic reaction.
What methocarbamol treats
Methocarbamol treats acute musculoskeletal pain and muscle spasm following a strain, sprain or similar injury, used alongside rest and physiotherapy. It is not a treatment for spasticity from neurological conditions, and it is not intended for long-term daily use. On its own it does not address the underlying injury, so pair it with rest, gentle stretching or physical therapy for lasting relief, and ask for reassessment if spasm persists beyond a few weeks.
How methocarbamol works
Methocarbamol depresses signaling within the central nervous system, between the brain, spinal cord and muscles, reducing the reflex activity that keeps a muscle tightly contracted. It does not act directly on the muscle tissue itself.
Before you take it
- Tell your prescriber about liver or kidney disease, epilepsy, or myasthenia gravis.
- Combining methocarbamol with alcohol, opioids, benzodiazepines, sleep aids or other sedating drugs increases drowsiness and the risk of dangerously slowed breathing.
- Avoid driving or operating machinery until you know how the drug affects you.
- Methocarbamol can turn urine green, black or brown; this is harmless and expected.
Side effects
Common effects include drowsiness, dizziness, headache and light-headedness on standing.
Stop and seek urgent medical care for:
- Rash, hives or facial swelling.
- Difficulty breathing or swallowing.
- A fast or pounding heartbeat.
- Severe dizziness with confusion.
Safety essentials
- Methocarbamol is sedating; avoid alcohol and other central-nervous-system depressants, since combining them intensifies drowsiness and can dangerously slow breathing.
- Do not drive or operate machinery until you know how it affects you.
- Harmless darkening of urine, green, black or brown, can occur and does not signal a problem.
This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.