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Carbacot Side Effects

Generic name: methocarbamol

Medically reviewed by Drugs.com. Last updated on Mar 12, 2025.

Note: This document provides detailed information about Carbacot Side Effects associated with methocarbamol. Some dosage forms listed on this page may not apply specifically to the brand name Carbacot.

Applies to methocarbamol: injection solution.

Other dosage forms:

Precautions

It is very important that your doctor check your progress closely while you are receiving this medicine. This will allow your doctor to see if the medicine is working properly and to check for unwanted effects.

Your doctor will only give you a few doses of this medicine until your condition improves, and then you will be switched to an oral medicine that works the same way. If you have any concerns about this, talk to your doctor.

Check with your doctor before using this medicine with alcohol or other medicines that affect the central nervous system (CNS). The use of alcohol or other medicines that affect the CNS with risperidone may worsen the side effects of this medicine, such as dizziness, poor concentration, drowsiness, unusual dreams, and trouble with sleeping. Some examples of medicines that affect the CNS are antihistamines or medicine for allergies or colds, sedatives, tranquilizers, or sleeping medicines, medicine for depression, medicine for anxiety, prescription pain medicine or narcotics, medicine for attention deficit and hyperactivity disorder, medicine for seizures or barbiturates, muscle relaxants, or anesthetics, including some dental anesthetics.

This medicine may cause some people to become dizzy or drowsy. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert.

Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.

The vial stopper of methocarbamol (the active ingredient contained in Carbacot) injection contains dry natural rubber (a derivative of latex), which may cause allergic reactions in people who are sensitive to latex. Tell your doctor if you have a latex allergy before you start using this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines) and herbal or vitamin supplements.

Serious side effects of Carbacot

Along with its needed effects, methocarbamol may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking methocarbamol:

Incidence not known

  • black, tarry stools
  • blurred vision
  • changes in skin color
  • chest pain or discomfort
  • chills
  • clay-colored stools
  • confusion
  • convulsions
  • cough
  • dark urine
  • difficulty swallowing
  • dizziness, faintness, or lightheadedness when suddenly getting up from a lying or sitting position
  • drowsiness
  • fast heartbeat
  • fever
  • headache
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • lightheadedness, dizziness, or fainting
  • loss of appetite
  • loss of bladder control
  • loss or problems with memory
  • muscle spasm or jerking of all extremities
  • nausea
  • pain, tenderness, or swelling of the foot or leg
  • painful or difficult urination
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • rash, hives, itching, red skin
  • slow or irregular heartbeat
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • stomach pain
  • sudden loss of consciousness
  • sweating
  • swollen glands
  • tightness in the chest
  • unpleasant breath odor
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vomiting of blood
  • yellow eyes or skin

Get emergency help immediately if any of the following symptoms of overdose occur while taking methocarbamol:

Symptoms of overdose

Other side effects of Carbacot

Some side effects of methocarbamol may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

  • belching
  • bleeding, blistering, burning, coldness, discoloration of skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
  • burning, dry, or itching eyes
  • discharge, excessive tearing
  • double vision
  • feeling of constant movement of self or surroundings
  • feeling of warmth
  • heartburn
  • indigestion
  • metallic taste
  • redness of the face, neck, arms, and occasionally, upper chest
  • redness, pain, or swelling of the eye, eyelid, or inner lining of the eyelid
  • sensation of spinning
  • stuffy nose
  • trouble sleeping
  • uncontrolled eye movements
  • vomiting

For healthcare professionals

Applies to methocarbamol: injectable solution, oral tablet.

General adverse events

The most commonly reported adverse reaction is headache.[Ref]

Cardiovascular

Some cardiovascular events may have been due to an overly rapid IV injection.

Most syncope cases resulted in spontaneous recovery; however, epinephrine, injectable steroids, and/or injectable antihistamines have been used in some cases.[Ref]

Hypersensitivity

Nervous system

Convulsions have been reported with IV administration in patients with seizure disorders.[Ref]

Psychiatric

Local

Dermatologic

Gastrointestinal

Other

Ocular

Hematologic

Hepatic

Respiratory

References

1. "Product Information. Robaxin (methocarbamol)." Whitehall-Robbins

2. "Multum Information Services, Inc. Expert Review Panel"

3. CAMPBELL DJ, SHERBANIUK R, RIGBY J (1964) "FALSE POSITIVE REACTION DUE TO METHOCARBAMOL IN THE SCREENING TEST FOR VANILMANDELIC ACID (VMA)." CLIN CHEM, 10, p. 447-50

Does Carbacot interact with my other drugs?

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Frequently asked questions

Further information

Carbacot side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.