Merbentyl Tablets

1. Name Of The Medicinal Product

Merbentyl 10mg Tablets

Merbentyl 20mg Tablets

2. Qualitative And Quantitative Composition

Dicycloverine hydrochloride 10mg or 20mg

3. Pharmaceutical Form

Tablets

4. Clinical Particulars

4.1 Therapeutic Indications

Smooth muscle antispasmodic primarily indicated for treatment of functional conditions involving smooth muscle spasm of the gastrointestinal tract.

4.2 Posology And Method Of Administration

Route of administration: Oral

10mg and 20mg tablets:

Adults and children over 12 years: 10-20mg three times daily before or after

meals.

10mg tablets only:

Children (2-12 years): 10mg three times daily.

4.3 Contraindications

Known idiosyncrasy to dicycloverine hydrochloride.

4.4 Special Warnings And Precautions For Use

Products containing dicycloverine hydrochloride should be used with caution in any patient with or suspected of having glaucoma or prostatic hypertrophy. Use with care in patients with hiatus hernia associated with reflux oesophagitis because anticholinergic drugs may aggravate the condition.

4.5 Interaction With Other Medicinal Products And Other Forms Of Interaction

None stated.

4.6 Pregnancy And Lactation

Epidemiological studies in pregnant women with products containing dicycloverine hydrochloride (at doses up to 40mg/day) have not shown that dicycloverine hydrochloride increases the risk of foetal abnormalities if administered during the first trimester of pregnancy. Reproduction studies have been performed in rats and rabbits at doses of up to 100 times the maximum recommended dose (based on 60mg per day for an adult person) and have revealed no evidence of impaired fertility or harm to the foetus due to dicycloverine. Since the risk of teratogenicity cannot be excluded with absolute certainty for any product, the drug should be used during pregnancy only if clearly needed.

It is not known whether dicycloverine is secreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when dicycloverine is administered to a nursing mother.

4.7 Effects On Ability To Drive And Use Machines

None stated.

4.8 Undesirable Effects

Side-effects seldom occur with Merbentyl tablets. However, in susceptible individuals, dry mouth, thirst and dizziness may occur. On rare occasions, fatigue, sedation, blurred vision, rash, constipation, anorexia, nausea and vomiting, headache and dysuria have also been reported.

4.9 Overdose

Symptoms of Merbentyl overdosage are headache, dizziness, nausea, dry mouth, difficulty in swallowing, dilated pupils and hot dry skin. Treatment may include emetics, gastric lavage and symptomatic therapy if indicated.

5. Pharmacological Properties

5.1 Pharmacodynamic Properties

Dicycloverine hydrochloride relieves smooth muscle spasm of the gastrointestinal tract.

Animal studies indicate that this action is achieved via a dual mechanism;

(1) a specific anticholinergic effect (antimuscarinic at the ACh-receptor sites) and

(2) a direct effect upon smooth muscle (musculotropic).

5.2 Pharmacokinetic Properties

After a single oral 20mg dose of dicycloverine hydrochloride in volunteers, peak plasma concentration reached a mean value of 58ng/ml in 1 to 1.5 hours. ¹⁴C labelled studies demonstrated comparable bioavailability from oral and intravenous administration. The principal route of elimination is via the urine.

5.3 Preclinical Safety Data

None stated.

6. Pharmaceutical Particulars

6.1 List Of Excipients

Lactose

Calcium Hydrogen Phosphate

Icing Sugar*

Maize Starch

Glucose Liquid**

Magnesium Stearate

Purified Water

* mixture of Sucrose 97%

Starch 3%

** equivalent to 4.8mg Glucose Solids

6.2 Incompatibilities

None stated.

6.3 Shelf Life

5 years.

6.4 Special Precautions For Storage

Do not store above 25°C.

6.5 Nature And Contents Of Container

Container: opaque blue 250 micron PVC blisters with aluminium foil 20 micron

Pack size 10mg tablets: 100 tablets.

Pack size 20mg tablets: 84 tablets

6.6 Special Precautions For Disposal And Other Handling

None stated.

7. Marketing Authorisation Holder

Sanofi-aventis

One Onslow Street

Guildford

Surrey, GU1 4YS, UK

8. Marketing Authorisation Number(S)

Merbentyl 10mg PL 04425/0035

Merbentyl 20mg PL 04425/0081

9. Date Of First Authorisation/Renewal Of The Authorisation

Date of first authorisation: Merbentyl 10mg - 27^th September 1982

Merbentyl 20mg - 13 February 1986

Date of renewal: Merbentyl 10mg - 14^th April 1994

Merbentyl 20mg - 13 February 1991

10. Date Of Revision Of The Text

November 2006

Legal category: POM