From the FDA Drug Label
CONTRAINDICATIONS Hypersensitivity to bethanechol chloride, hyperthyroidism, peptic ulcer, latent or active bronchial asthma, pronounced bradycardia or hypotension, vasomotor instability, coronary artery disease, epilepsy and parkinsonism Bethanechol chloride should not be employed when the strength or integrity of the gastrointestinal or bladder wall is in question, or in the presence of mechanical obstruction; when increased muscular activity of the gastrointestinal tract or urinary bladder might prove harmful, as following recent urinary bladder surgery, gastrointestinal resection and anastomosis, or when there is possible gastrointestinal obstruction; in bladder neck obstruction, spastic gastrointestinal disturbances, acute inflammatory lesions of the gastrointestinal tract, or peritonitis; or in marked vagotonia. The contraindications to bethanechol are:
- Hypersensitivity to bethanechol chloride
- Hyperthyroidism
- Peptic ulcer
- Latent or active bronchial asthma
- Pronounced bradycardia or hypotension
- Vasomotor instability
- Coronary artery disease
- Epilepsy and parkinsonism
- Conditions where the strength or integrity of the gastrointestinal or bladder wall is in question
- Mechanical obstruction
- Recent urinary bladder surgery, gastrointestinal resection and anastomosis, or possible gastrointestinal obstruction
- Bladder neck obstruction
- Spastic gastrointestinal disturbances
- Acute inflammatory lesions of the gastrointestinal tract
- Peritonitis
- Marked vagotonia 1
From the Research
Bethanechol is contraindicated in several conditions where stimulation of muscarinic receptors could worsen the underlying pathology, including mechanical obstruction of the gastrointestinal or urinary tract, active bronchial asthma, hyperthyroidism, peptic ulcer disease, and cardiac disease. These contraindications are due to the potential for bethanechol to exacerbate conditions characterized by increased smooth muscle tone, altered autonomic function, or where increased secretions would be detrimental 2. The medication should not be used in patients with:
- Mechanical obstruction of the gastrointestinal or urinary tract, as bethanechol's stimulatory effects on smooth muscle could increase pressure against the obstruction and potentially cause rupture
- Active bronchial asthma due to the risk of bronchospasm
- Hyperthyroidism, peptic ulcer disease, inflammatory bowel disease, pronounced bradycardia or hypotension, vasomotor instability, cardiac disease (including recent myocardial infarction, heart failure, and coronary artery disease), epilepsy, and Parkinson's disease
- Bethanechol should be avoided during pregnancy, especially the first trimester, and in patients with known hypersensitivity to the drug It is essential to carefully assess the patient's medical history and current condition before prescribing bethanechol to minimize the risk of adverse effects. The most recent study on bethanechol, published in 2019, highlights its continued use in elderly women primarily for detrusor atony, urinary retention, or incomplete bladder emptying 2. However, the study does not provide information on contraindications, which are primarily based on the drug's mechanism of action and potential to exacerbate certain conditions. In clinical practice, it is crucial to prioritize the patient's safety and well-being by avoiding the use of bethanechol in conditions where it may cause harm.