Adult: The recommended oral dose is 10-50 mg 3-4 times/day. It is also given in the form of subcutaneous (under the skin) injection by administering a dose of 5 mg 3-4 times/day. The dose is fixed based on the type and severity of the condition to be treated.
Gastrointestinal - Nausea, vomiting, belching, increased salivation, abdominal cramps and diarrhea.
Genitourinary - Frequent urge to urinate.
Respiratory - Difficulty in breathing, precipitation of asthmatic attacks.
Central Nervous System:Dizziness, light headedness, headache.
Heart: Low blood pressure with fast heart rate, feeling faint.
Eye: Watering of eyes, problems with vision.
Skin – Flushing of skin due to dilatation of blood vessels, sweating, rashes in case of allergy.
It comes as a tablet to be taken by mouth with a full glass of water. It should be taken on an empty stomach one hour before meals or two hours after meals to avoid nausea and vomiting. It is also available as an elixir and solution for injection.
Bethanechol is contraindicated in patients who are allergic to the drug, with history of asthma, peptic ulcer, intestinal or urinary obstruction, following recent gastrointestinal or urinary surgery, decreased heart rate and low blood pressure, epilepsy, Parkinsonism, coronary heart disease and overactive thyroid.
Avoid excess dosage.
Consult the doctor immediately if any serious adverse effects occur like tightness in the chest or difficulty with breathing.
Bethanechol should be avoided with:
Ganglion blocking compounds as it can cause severe lowering of blood pressure.
Drugs which are used for the treatment of Alzheimer’s disease like donepezil, tacrine due to the additive side effects like increased saliva, bowel movements, blurred vision and urination.
Store it in a closed container at room temperature. Protect from heat, light and excess moisture. Keep away from children.