[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Gabapentinoids](https://durgical.com/en/pharmacology/classes/gabapentinoids/) › Gabapentin

[Pharmacology](https://durgical.com/en/pharmacology/) · [Gabapentinoids](https://durgical.com/en/pharmacology/classes/gabapentinoids/)

# Gabapentin

A nerve-pain and add-on seizure medicine that binds a calcium channel subunit. It causes drowsiness and dizziness and leaves the body by the kidneys.

Updated 2026-11-01

- Class: [Gabapentinoids](https://durgical.com/en/pharmacology/classes/gabapentinoids/)
- Ion channel: α2δ-1 subunit of voltage-gated calcium channels
- ATC code: N02BF01

⇅**α2δ-1 subunit of voltage-gated calcium channels**Gabapentin

ⓘ The figure shows gabapentin bound to the α2δ-1 subunit (from rabbit) in a complex with the human Cav1.2 calcium channel.

**Target in 3D:** α2δ-1 subunit of voltage-gated calcium channels. PDB structure 8FD7 (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/8FD7) · Drag to rotate · pinch to zoom

## Mechanism of action

Gabapentin looks like GABA but does not act on GABA receptors or GABA metabolism. It binds the α2δ-1 subunit of voltage-gated calcium channels, which is thought to reduce calcium entry at overactive nerve terminals and the release of excitatory transmitters.

- Binds the α2δ-1 subunit of voltage-gated calcium channels
- Fewer active channels at presynaptic terminals
- Less release of excitatory transmitters
- Nerve pain and seizure spread are dampened

## Pharmacokinetics

**Absorption**
Absorbed by mouth; aluminium or magnesium antacids reduce absorption

**Metabolism**
Not metabolized

**Elimination**
Unchanged in the urine; the dose is adjusted in kidney disease

**Half-life**
About 5 to 7 hours

## Indications

- Postherpetic neuralgia (pain after shingles) [Herpes zoster (shingles) →](https://durgical.com/en/conditions/herpes-zoster/)
- Add-on treatment of focal seizures [Epilepsy and seizures →](https://durgical.com/en/conditions/epilepsy-and-seizures/)

## Adverse effects

### Common

- Drowsiness
- Dizziness
- Unsteadiness (ataxia)

### Serious (rare, important)

- Respiratory depression with opioids or other sedatives, or with respiratory impairment
- Anaphylaxis and angioedema
- DRESS (multi-organ hypersensitivity)
- Emotional and behavioural changes in children
- Suicidal thoughts

## Contraindications

- Hypersensitivity to gabapentin

## Key interactions

**Opioids and other central nervous system depressants**
Serious, sometimes fatal respiratory depression

**Aluminium or magnesium antacids**
Less gabapentin absorbed; it is usually separated from them

**Alcohol**
More drowsiness and dizziness

## What is monitored

- Sedation and breathing, especially with opioids
- Kidney function
- Mood and suicidal thoughts
- Signs of misuse

## Administration and safety

- Given by mouth
- Separated from aluminium or magnesium antacids
- Withdrawn gradually

## Nursing care

- Check sedation and breathing, especially when an opioid is also given
- Teach about dizziness and the risk of falls
- Teach to report rash, fever or facial swelling
- Ask about kidney disease before the first dose

## Pregnancy and breastfeeding

Human data are limited; a neonatal withdrawal syndrome has been reported after exposure in pregnancy.

## Memory aid

Gabapentin: «GABA in name only» – it binds α2δ, not GABA receptors, and leaves by the kidneys untouched.

## Test yourself

Think of the answer, then tap the question to see it.

## Does gabapentin act on GABA receptors?

No. Despite its GABA-like structure it binds the α2δ-1 subunit of voltage-gated calcium channels.

## Which pain condition is a labelled indication of gabapentin?

Postherpetic neuralgia, the pain that can persist after shingles.

## Why must gabapentin be used carefully with opioids?

The combination can cause serious, even fatal, respiratory depression.

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/gabapentin/)

## Related drugs

- [Pregabalin](https://durgical.com/en/pharmacology/pregabalin/)

## Related conditions

- [Herpes zoster (shingles)](https://durgical.com/en/conditions/herpes-zoster/)
- [Epilepsy and seizures](https://durgical.com/en/conditions/epilepsy-and-seizures/)

[← Back to the class: Gabapentinoids](https://durgical.com/en/pharmacology/classes/gabapentinoids/)

Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: [Gabapentin: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a694007.html) (MedlinePlus (U.S. National Library of Medicine), 2020); [DailyMed - GABAPENTIN capsule](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=16542ee6-0e0e-4d3c-8b32-60ff6ef48846) (DailyMed (U.S. National Library of Medicine), 2026); [ATCDDD - ATC/DDD Index](https://atcddd.fhi.no/atc_ddd_index/?code=N02BF01) (WHO Collaborating Centre for Drug Statistics Methodology, 2026).

## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake

Representative model, for educational purposes only.

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Source: https://durgical.com/en/pharmacology/gabapentin/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/gabapentin/