Methocarbamol: what it treats, how to take it, side effects
Last updated September 3, 2026.
Methocarbamol is a muscle relaxant - it slows activity in the nervous system to let the body release a seized muscle. You may know it as Robaxin. It is one part of a team: the drug plus rest, physical therapy, and time.
What does it treat?
Pain and discomfort from strains, sprains, and other muscle injuries - used with rest, physical therapy, and other measures. It relaxes the muscle spasm that keeps an injury locked up; it does not heal the injury itself.
How do you take it?
Tablets on the schedule your prescriber writes, typically three or four times a day at the start of an injury, then tapering as the muscle releases. It causes drowsiness and dizziness - learn your response before driving, and skip alcohol, which stacks the sedation. Missed dose: take it when you remember unless the next one is close; never double up.
Side effects to know
- Common: drowsiness, dizziness, upset stomach, blurred vision, fever - and the famous one: black, blue, or green discoloration of the urine, which is harmless and reverses when the drug stops.
- Serious - call your doctor immediately: rash and itching.
Who should not take it?
Anyone allergic to it. Flag kidney or liver problems and any seizure history before starting. Other sedating medications - sleep aids, anti-anxiety drugs, opioids - stack with it, so the full medication list matters. If you become pregnant, call your doctor.
When is it an emergency?
A spreading rash, facial swelling, or trouble breathing is urgent care. For an overdose, call Poison Control at 1-800-222-1222. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
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Common questions
Why is my urine green on methocarbamol?
The drug's harmless party trick: black, blue, or green urine discoloration is on the common-effects list. It is a metabolite passing through, not blood, not infection, and it reverses when the medication stops. Nothing to do but know it is coming - and it makes a good reminder that you are, in fact, on the medication.
Why did my doctor prescribe rest and PT with a muscle relaxer?
Because methocarbamol does not heal anything - MedlinePlus says it is used with rest, physical therapy, and other measures. The muscle spasm is your body guarding the injury; the drug releases the guard so the injury can actually recover and the PT can actually happen. Pill alone: temporary relief, same injury. Pill plus the program: healing.
Why can't I drive right after taking it?
Drowsiness, dizziness, and blurred vision lead the common-effects list - the nervous-system slowing that releases your muscle slows your reactions too. Until you know how your body handles each dose, no driving and no machinery. Most people map their drowsy window within a few doses and plan around it.
Can I have a beer with methocarbamol?
Skip it. Both slow the nervous system, and the combination stacks sedation past either one alone - the same reason sleep aids, anti-anxiety medications, and opioids get flagged. For the week or two of a typical course, the beer waits. Your prescriber is the one to ask if the course extends.
How long do I stay on methocarbamol?
As long as the prescriber wrote it - typically days to a couple of weeks, covering the acute spasm window. It is not a maintenance drug; strains and sprains heal, and the prescription ends when they do. Pain that outlasts the course is a re-evaluation, not a refill - something else may be going on in there.
What happens if I miss a dose of methocarbamol?
Take it as soon as you remember, unless it is almost time for the next one - then skip it and never double up. Doubling stacks the drowsiness and dizziness, and since the injury is healing on a schedule anyway, one missed dose costs little.