- bethanechol chloride
POM: Prescription only medicine
This information is intended for use by health professionals
Myotonine Tablets 25 mg
Each 25 mg tablet weighs 440 mg; total active ingredient 25 mg bethanechol chloride USPXXIV.
For the full list of excipients, see section 6.1.
Each 25 mg tablet is white, flat with bevelled edge and with a cross score and the embossment “MY25”.
Urinary retention -acute postoperative, postpartum and neurogenic.
The experience with children is limited; therefore no recommended dose is given.
10 mg - 25 mg 3-4 times daily. Taken ½ hr before food.
Occasionally it may be felt necessary to initiate therapy with a 50 mg dose.
Adult dosage administered with caution.
Method of administration
Administration orally by tablets.
Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.
Intestinal or urinary obstruction, recent myocardial infarction, recent intestinal anastomosis.
A severe cholinergic reaction is likely to occur if bethanechol chloride is administered IV or IM. This reaction has also rarely occurred in cases of hypersensitivity or overdose.
Pharmacological interactions may occur with the following when bethanechol is administered. Quinidine and procainamide which may antagonise cholinergic effects, cholinergic drugs which may have an additive effect, particularly cholinesterase inhibitors.
When administered to patients receiving ganglionic blocking compounds, a critical fall in blood pressure may occur preceded by severe abdominal symptoms.
Should not be used during pregnancy or lactation.
In some cases the ability to drive and operate machinery may be impaired.
Nausea, vomiting, sweating and intestinal colic.
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 at: www.mhra.gov.uk/yellowcard.
Symptoms: Include nausea, salivation, lachrymation, eructation, involuntary defecation and urination, transient dyspnoea, palpitation, bradycardia and peripheral vasodilation leading to hypertension, transient heart block and a feeling of constriction under the sternum.
Procedure: The stomach should be emptied by aspiration and lavage.
Give atropine sulphate 1-2 mg intravenously, intramuscularly or subcutaneously to control muscarinic effects. This dose may be repeated every 2-4 hours as necessary.
Supportive treatment includes intravenous administration of diazepam 5-10 mg, muscle twitching may be controlled by small doses of tubocararine (together with assisted respiration), oxygen may be required.
Pharmacotherapeutic group: Parasympathomimetics, Choline esters, Bethanechol,
ATC code: N07AB02
Mechanism of action
Bethanechol is a synthetic choline ester of carbamic acid which possesses a significant acetyl choline-like activity. It is active after oral administration. As a consequence of the very slow hydrolysation by acetylcholinesterase, bethanechol has a prolonged action as has been demonstrated on the urinary tract. The onset of action after oral administration of bethanechol chloride occurs within one hour.
The major pharmacological effects of bethanechol result from interaction of the drug with muscarinic receptor sites of smooth muscles, especially those of the urinary bladder and gastrointestinal tract. In addition, minor but important nicotinic effects have been noted.
In usual therapeutic doses, bethanechol does not cross the blood brain barrier.
Studies addressing pharmacokinetic-pharmacodynamic association are not available.
Calcium sulfate dihydrate BP
Maize starch BP
Purified talc BP
Keep out of reach of children.
The container consists of blister strips of PVC/aluminium foil packed in boxes.
Each container holds 100 tablets.
04 December 1973 / 20 March 2015
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+49 (0)89 189 353 63
+49 (0)3834 51 47 186
+49 (0)3834 51 47 186