Symptomatic treatment of painful muscular tension, especially in the lower back (lumbago)

Methocarbamol is indicated in adults

Posology

Adults: The usual dose is 2 tablets four times daily but therapeutic response has been achieved with doses as low as 1 tablet three times daily.

Elderly: Half the maximum dose or less may be sufficient to produce a therapeutic response.

Paediatric population

Not recommended.

Hepatically impaired

In patients with chronic hepatic disease the elimination half-life may be prolonged. Therefore, consideration should be given to increasing the dose interval.

Method of administration

For oral use.

Take the film-coated tablets with sufficient water.

Hypersensitivity to methocarbamol or to any of the excipients listed in section 6.1.

• Coma or pre-coma states

• Central nervous system disorders

• Myasthenia gravis

• Patients with a tendency to epileptic cramps

Methocarbamol should be used with caution in patients with renal and hepatic insufficiency.

This medicine contains less than 1 mmol sodium (23 mg) per film-coated tablet, that is to say essentially 'sodium-free'.

Interference with laboratory tests

Methocarbamol may cause colour interference in certain screening tests for 5-hydroxyindolacetic acid (5-HIAA) and vanillylmandelic acid (VMA)

If methocarbamol is used concomitantly with centrally acting drugs such as barbiturates, opioids and appetite suppressants, the effects can be mutually enhanced.

The consumption of alcohol during treatment with methocarbamol can increase the effect.

The effects of anticholinergics, such as atropine and some psychotropic drugs, may be potentiated by methocarbamol.

Methocarbamol may reduce the effect of pyridostigmine bromide. Therefore, methocarbamol should not be used by patients with myasthenia gravis, particularly those being treated with pyridostigmine.

Pregnancy

There is no experience with the use of methocarbamol during pregnancy .There are no data from animal studies related to effects on pregnancy , embryonal/foetal development, parturition and postnatal development ( see section 5.3). the potential risk for humans is unknown. Therefore methocarbamol should not be used during pregnancy.

Breastfeeding

It is not known whether methocarbamol and/or its metabolites are excreted in human milk. Methocarbamol and/or its metabolites are excreted in the milk of lactating dogs Methocarbamol should therefore not be used during breastfeeding.

Fertility

No data are available on the influence of methocarbamol on human fertility.

Methocarbamol has moderate influence on the ability to drive and to use machines. Methocarbamol can cause dizziness or drowsiness, especially if other medicines that can also cause drowsiness are being taken at the same time..

Patients should be advised not to perform these activities if they experience dizziness or drowsiness.

The frequency information on side effects is based on the following categories (where it has been possible to obtain frequency data from the literature):

Very common ≥ 1/10

Common ≥ 1/100 to < 1/10

Uncommon ≥ 1/1,000 to < 1/100

Rare ≥ 1/10,000 to < 1/1,000

Very rare < 1/10,000

Not known The frequency cannot be estimated from the available data

The following adverse reactions have been reported with the use of methocarbamol:

*Localized, transient sensory disturbance primarily affecting the head (e.g. face, scalp), the mouth region (e.g. lips, tongue) or the extremities (hands, fingers, feet)

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Limited information is available on the acute toxicity of methocarbamol. Overdose of methocarbamol is frequently in conjunction with alcohol or other CNS depressants and includes the following symptoms: nausea, drowsiness, blurred vision, hypotension, seizures and coma. One adult survived the deliberate ingestion of 22 to 30 grams of methocarbamol without serious toxicity. Another adult survived a dose of 30 to 50 grams. The principal symptom in both cases was extreme drowsiness. Treatment was symptomatic and recovery was uneventful. However, there have been cases of fatal overdose.

Management of overdose includes symptomatic and supportive treatment. Supportive measures include maintenance of an adequate airway, monitoring urinary output and vital signs, and administration of intravenous fluids if necessary. The usefulness of haemodialysis in managing overdose is unknown.

Pharmacotherapeutic group: Muscle relaxants, centrally acting agents; Carbamic acid esters, ATC code: M03BA03.

Mechanism of action

Methocarbamol is a centrally acting muscle relaxant.

Pharmacodynamic effects

It exerts its myorelaxant effect by inhibiting the polysynaptic reflexes in the spinal cord and subcortical centres.

Clinical efficacy and safety

The physiological tonus, contractility of the skeletal muscles, and the motility of smooth muscles are not impaired by methocarbamol at therapeutic doses and there is no effect on the motor endplate.

Absorption

After oral administration, methocarbamol is rapidly and completely absorbed. .

Distribution

The active substance is already detectable in the blood 10 minutes after ingestion, and the peak blood concentration is reached after 30 - 60 minutes.

The plasma half-life of methocarbamol is approximately 2 hours.

Biotransformation and Elimination

Methocarbamol and its two main metabolites are bound to glucuronic and sulfuric acid and excreted almost exclusively via the kidney. About half of the applied dose is excreted with the urine within 4 hours, only a small part of it as unchanged methocarbamol.

Renally impaired

In patients with renal impairment undergoing long-term hemodialysis treatment, the clearance of methocarbamol was reduced by approximately t 40% compared to a population with normal renal function, although the mean elimination half-life in these two groups was similar (1.2 versus 1.1 hours, respectively).

Hepatically impaired

In patients with alcoholic cirrhosis, the mean total clearance of methocarbamol was decreased approximately 70% compared to a normal population (11.9 L/hr), and the mean elimination half-life was increased to approximately 3.4 hours. The proportion of methocarbamol bound to plasma proteins was about 40 to 45% reduced compared to 46 to 50% in an age and weight control population normal liver function.

The acute toxicity of methocarbamol is comparatively low. Signs of intoxication in animal studies include ataxia, catalepsy, convulsions and coma.

Studies on chronic toxicity and on reproductive toxicity have not been performed.

In vitro and in vivo genetic toxicology studies with methocarbamol did not provide any indication of a mutagenic potential.

Long-term studies to clarify a carcinogenic potential were not carried out.

Tablet core

Maize starch

Sodium starch glycolate (Type – A)

Povidone (K-30)

Sodium laurilsulfate

Talc

Magnesium stearate

Tablet coat

Hypromellose 2910 (6 mPas)

Titanium dioxide

Macrogol 400

Not applicable.

3 years.

This medicinal product does not require any special storage conditions.

White opaque round HDPE container with 38mm neck finish closed with 38mm white opaque polypropylene stock ribbed (i.e. continuous thread) closure with wad having induction sealing liner.

Pack size: 100 film-coated tablets.

Any unused medicinal product or waste material should be disposed of in accordance with local requirements.