What is the recommended dosage of Campral (Acamprosate) for patients with impaired renal function?

Acamprosate (Campral) Dosing in Renal Impairment

For patients with moderate renal impairment (creatinine clearance 30-50 mL/min), acamprosate should be dosed at 333 mg three times daily, which is a 50% reduction from the standard dose. 1

Standard Dosing

• The recommended standard dose of acamprosate for patients with normal renal function is 666 mg (two 333 mg tablets) taken three times daily 1
• Treatment should be initiated as soon as possible after alcohol withdrawal when the patient has achieved abstinence 1
• Dosing may be done without regard to meals, though taking with meals was employed during clinical trials 1

Renal Impairment Dosing Algorithm

• Normal renal function: 666 mg (two 333 mg tablets) three times daily 1
• Moderate renal impairment (creatinine clearance 30-50 mL/min): 333 mg (one tablet) three times daily 1
• Severe renal impairment (creatinine clearance ≤30 mL/min): Acamprosate is contraindicated 1

Pharmacokinetic Considerations

• Acamprosate is not metabolized by the liver and is excreted unchanged in urine 1
• In patients with moderate renal impairment, peak plasma concentrations are approximately 2-fold higher compared to healthy subjects 1
• In patients with severe renal impairment, peak plasma concentrations are approximately 4-fold higher compared to healthy subjects 1
• The elimination half-life is prolonged by approximately 1.8-fold in moderate renal impairment and 2.6-fold in severe renal impairment 1
• There is a linear relationship between creatinine clearance values and total apparent plasma clearance, renal clearance, and plasma half-life of acamprosate 1

Clinical Considerations

• Renal function should be assessed before initiating acamprosate therapy 1
• Acamprosate should be used as part of a comprehensive psychosocial treatment program 1
• Treatment should be maintained if the patient relapses 1
• No adjustment of dosage is needed for patients with mild to moderate hepatic impairment as acamprosate is not metabolized by the liver 1, 2

Safety Considerations

• Acamprosate has a low propensity for drug interactions 3
• The most common adverse effects include diarrhea, nausea, and gastrointestinal distress 4
• Suicidal ideation and depression have been reported more frequently in acamprosate-treated patients than in placebo-treated patients 1
• Acamprosate does not produce withdrawal symptoms and does not cause a disulfiram-like reaction with alcohol 1

Monitoring

• Regular monitoring of renal function is advisable in patients with moderate renal impairment 1
• Monitor for signs of suicidality and depression 1
• No routine laboratory monitoring is required specifically for acamprosate therapy 4