What is the recommended dosing of eloxadoline for an adult with irritable bowel syndrome with diarrhea (IBS-D), and how should the dose be adjusted in cases of cholecystectomy, mild hepatic impairment, or intolerance?

Eloxadoline Dosing for IBS-D

The standard dose of eloxadoline for adults with IBS-D is 100 mg twice daily with food, but you must reduce to 75 mg twice daily in patients with mild-to-moderate hepatic impairment, those unable to tolerate the 100 mg dose, or those taking OATP1B1 inhibitors. 1

Standard Dosing

• 100 mg twice daily is the FDA-approved dose for most adults with IBS-D 1
• Take with food
• This dose showed sustained efficacy over 6 months in clinical trials 2

Dose Reduction to 75 mg Twice Daily Required For:

Three specific situations mandate the lower dose:

1. Mild or moderate hepatic impairment 1
2. Intolerance to the 100 mg dose (most commonly constipation, nausea, or abdominal pain) 1
3. Concomitant use of OATP1B1 inhibitors 1

Additional Populations Where 75 mg May Be Preferred:

• Patients ≥65 years: Subgroup analysis showed greater response rates with 75 mg compared to 100 mg in elderly patients, contrary to the overall population 3
• Severe renal impairment or end-stage renal disease (not yet on dialysis): Systemic exposure increases 2.2-fold in these patients, warranting the lower dose as a precautionary measure 4

Absolute Contraindications - Do NOT Prescribe:

Eloxadoline is absolutely contraindicated in patients without a gallbladder (post-cholecystectomy). 1 This is critical—all cases of sphincter of Oddi spasm in clinical trials occurred in patients without a gallbladder, typically within the first week of treatment 5.

Additional contraindications:

• Consumption of >3 alcoholic beverages per day 1
• History of pancreatitis or known pancreatic duct obstruction 6
• History of biliary duct obstruction or sphincter of Oddi dysfunction 6
• Severe hepatic impairment 6
• Severe or chronic constipation 6
• Known mechanical GI obstruction 6

Critical Safety Considerations:

Pancreatitis risk: 5 cases occurred in 1,666 patients (0.3%) in phase 3 trials, with 3 associated with heavy alcohol use and all others in patients without gallbladders 1, 5. Most sphincter of Oddi events (8/10) occurred with the 100 mg dose within the first week 5.

Common adverse events (occurring in 7-8% of patients):

• Constipation (8%)
• Nausea (7%)
• Abdominal pain (7%)

These are generally mild, with discontinuation due to constipation occurring in only 1.1-1.5% of patients 1

Clinical Pitfalls to Avoid:

1. Never prescribe to post-cholecystectomy patients—this is the single most important safety consideration
2. Screen for alcohol use before prescribing
3. Start with 75 mg in elderly patients (≥65 years) given their superior response to this dose
4. Consider the lower dose in patients with severe renal impairment
5. Be vigilant for acute abdominal pain in the first week of treatment, particularly with the 100 mg dose