Medication Reference Card: Alcohol Use Disorder

Gabapentin

900–1800 mg/day in 3 divided doses · Especially useful in withdrawal-sensitive AUD · Off-label (AUD)

Dr Basanth Kenchaiah
FRANZCP · Cert. Addiction Psych. · MBBS · DPM · DNB (Psychiatry) Addiction Psychiatrist v1.2 · October 2026

Audience Clinicians

Purpose Prescribing quick-reference for gabapentin in alcohol use disorder (AUD): off-label use.

Key messages

Alpha-2-delta calcium channel ligand; attenuates glutamate hyperactivity, reduces craving and withdrawal
900–1800 mg/day in divided doses; taper slowly to avoid gabapentin withdrawal; best evidence at 1800 mg/day
Monitor for sedation, dependence, and respiratory risk especially with concurrent CNS depressants or opioids

For Patients

Gabapentin is a medication primarily used for nerve pain and epilepsy, but there is evidence it can help reduce alcohol use, particularly in people who experience significant physical withdrawal symptoms or who have trouble sleeping when they stop drinking.

Particularly useful when comorbid with:

Alcohol withdrawal history / withdrawal kindling Post-acute withdrawal syndrome (PAWS) with insomnia and anxiety Neuropathic pain / fibromyalgia (dual benefit) Restless leg syndrome Benzodiazepines contraindicated (acute withdrawal adjunct)

For Clinicians

Mechanism

Binds to voltage-gated calcium channel alpha-2-delta subunit, reducing glutamate release and neuronal excitability. Modulates GABA activity indirectly. Reduces alcohol withdrawal kindling and post-acute withdrawal symptoms. Anxiolytic and hypnotic properties directly relevant to early AUD recovery.

Dosing

Standard: 900–1800 mg/day in 3 divided doses (titrate from 300 mg nocte). Some studies use up to 1800–3600 mg/day for severe withdrawal presentations. Renal dose reduction required (CrCl-based: see product information). Off-label for AUD in Australia. Document clinical reasoning.

Evidence

Low-to-moderate evidence overall. Mason et al. JAMA Intern Med 2014: gabapentin 1800 mg/day significantly increased abstinence (17% vs 4% placebo); 41% abstinence in high-withdrawal subgroup vs 1% placebo. McPheeters et al. JAMA 2023 meta-analysis: lower evidence strength than naltrexone or acamprosate for overall AUD but notably stronger in withdrawal-sensitive subgroups.

Cautions

Diversion and misuse potential: scheduling varies by state (check current state legislation)
Respiratory depression risk with concurrent opioids or alcohol: avoid combination or monitor closely
Sedation, dizziness, peripheral oedema: common at initiation
Abrupt discontinuation can precipitate withdrawal: taper when stopping
Avoid prescribing unsupervised to patients with active heavy drinking without a clear plan
Pregabalin (similar class) has higher misuse potential: use cautiously