When can a patient start Campral (Acamprosate) during substance detox?

When to Start Campral (Acamprosate) During Alcohol Detox

Acamprosate should be initiated 3-7 days after the last alcohol consumption and only after withdrawal symptoms have completely resolved—never during active detoxification. 1, 2

Critical Timing Requirements

Do not start acamprosate during active withdrawal. The medication is designed to maintain abstinence, not to treat withdrawal symptoms or induce initial abstinence. 1, 2, 3

Step-by-Step Algorithm:

1. Complete alcohol withdrawal management first using benzodiazepines (the gold standard for managing withdrawal syndrome and preventing seizures/delirium tremens). 4

2. Wait 3-7 days after the last alcohol consumption to ensure the patient has achieved complete abstinence. 1, 2

3. Confirm withdrawal symptoms have fully resolved before initiating acamprosate—this is an absolute requirement per FDA labeling. 2

4. Initiate acamprosate as soon as possible after the withdrawal period ends and abstinence is achieved. 2

Dosing Specifications

• Standard dose: 666 mg (two 333 mg tablets) three times daily for patients ≥60 kg 1, 2
• Reduced dose: Decrease by one-third for patients <60 kg 1
• Renal impairment: 333 mg three times daily for creatinine clearance 30-50 mL/min 1, 2
• Contraindication: Severe renal impairment (CrCl ≤30 mL/min) 2

Why This Timing Matters

Acamprosate works by modulating NMDA receptor transmission to reduce craving and maintain abstinence—it does not address acute withdrawal physiology. 1, 5 Starting it too early (during active withdrawal) reduces efficacy because its mechanism is designed for maintaining rather than inducing remission. 1, 3

The drug reaches steady-state plasma concentrations after 5-7 days of dosing, which aligns with the post-detoxification period when patients are most vulnerable to relapse. 6

Evidence Quality

This recommendation is based on moderate-quality evidence from the 2020 BMJ network meta-analysis showing acamprosate is the only intervention with sufficient evidence for maintaining abstinence up to 12 months post-detoxification. 7 The FDA label explicitly states efficacy has not been demonstrated in patients who have not undergone detoxification and achieved abstinence prior to treatment. 2

Common Pitfalls to Avoid

• Never start during active withdrawal—this delays appropriate benzodiazepine therapy and provides no benefit for withdrawal symptoms. 1, 4
• Do not use acamprosate as monotherapy—it must be combined with comprehensive psychosocial support programs for optimal efficacy. 1, 2
• Avoid premature discontinuation—treatment should continue for at least 3-6 months (up to 12 months) even if the patient relapses. 1, 2

Advantages Over Naltrexone

Unlike naltrexone, acamprosate is not metabolized by the liver, making it the preferred choice for patients with alcoholic liver disease or cirrhosis. 1, 5 Naltrexone carries hepatotoxicity risk and should never be used in patients with significant liver disease. 4, 5