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 · MBBS · DPM · DNB (Psychiatry) · Cert. Addiction Psych. Addiction Psychiatrist v1.0 · May 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. Jonas 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