From the FDA Drug Label
- 6 Renal Impairment Effects of renal impairment on PK, safety and efficacy of dicyclomine hydrochloride have not been studied. Dicyclomine hydrochloride drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Dicyclomine hydrochloride should be administered with caution in patients with renal impairment.
Use with Caution: Bentyl (dicyclomine) should be administered with caution in patients with Chronic Kidney Disease (CKD) stage 4, as the risk of toxic reactions may be greater in patients with impaired renal function 1.
- Key Consideration: The effects of renal impairment on the pharmacokinetics, safety, and efficacy of dicyclomine hydrochloride have not been studied.
- Clinical Decision: Given the lack of specific studies on CKD stage 4 patients, it is recommended to exercise caution when using Bentyl in this population.
From the Research
Bentyl (dicyclomine) can be used with caution in patients with CKD stage 4, but dose adjustments may be necessary to minimize the risk of adverse effects. The medication is primarily metabolized by the liver and excreted through both renal and biliary routes, with approximately 20% eliminated unchanged in urine. For patients with CKD stage 4, consider starting at a lower dose, such as 10 mg three times daily instead of the standard 20 mg four times daily, and monitor closely for adverse effects, as suggested by the most recent and highest quality study available 2. Common side effects to watch for include:
- Dry mouth
- Blurred vision
- Constipation
- Urinary retention
- Confusion which may be more pronounced in patients with kidney disease. These anticholinergic effects can be particularly problematic in elderly CKD patients. Regular monitoring of kidney function is recommended during treatment, as the use of anticholinergic medications like Bentyl in patients with CKD requires careful consideration of the potential risks and benefits, as highlighted in studies on the safety and efficacy of various medications in patients with CKD 3, 4. If the patient experiences worsening symptoms or signs of toxicity, further dose reduction or discontinuation may be necessary. The medication should be used for the shortest duration needed to control symptoms of irritable bowel syndrome or other gastrointestinal spasms, as prolonged use in advanced kidney disease has not been well studied, and the potential risks of anticholinergic toxicity must be carefully weighed against the potential benefits of treatment, as discussed in the context of belladonna alkaloid intoxication 5, 6.