Gabapentin 100mg/5ml oral solution
Requires a prescription from a doctor or prescriber
Antiepileptic drugs
Some safe custody exemptions; written records required
Legal requirements and restrictions
Schedule 3 medicines that do not require locked storage or register entries.
Legal requirements
- Prescriptions valid for 28 days
- No controlled drugs register required
- No safe custody (locked storage) required
Other medicines in this category
Official documents, adverse reaction reporting, and safety monitoring
Report a side effect
Submit a Yellow Card report to the MHRA
Official medicine documents
Safety monitoring data
Yellow Card reports
The MHRA Yellow Card scheme collects reports of suspected side effects from healthcare professionals and patients. View the Drug Analysis Profile (iDAP) for real-world adverse reaction data.
View Drug Analysis Profile
Suspected adverse reactions reported for Gabapentin
Browse all iDAP reports
Interactive Drug Analysis Profiles for all medicines
Report a side effect
Submit a Yellow Card report to the MHRA
Data from the MHRA Yellow Card scheme. A reported reaction does not necessarily mean the medicine caused it. Contains public sector information licensed under the Open Government Licence v3.0.
EudraVigilance
The European Medicines Agency (EMA) collects suspected adverse reaction reports from across the EU/EEA through the EudraVigilance system. Search for safety data on this medicine.
View EudraVigilance report
Suspected adverse reactions reported for Gabapentin
About EudraVigilance
Learn about EU pharmacovigilance and safety monitoring
EudraVigilance data is published by the European Medicines Agency (EMA). A suspected adverse reaction is not necessarily caused by the medicine.
1 branded products available
This is the NHS Drug Tariff indicative price used for reimbursement purposes. It may not reflect the price paid by patients or pharmacies.
View full Drug TariffSource: NHS Drug Tariff via NHSBSA. Derived from dm+d VMPP (Virtual Medicinal Product Pack) pricing data. Contains public sector information licensed under the Open Government Licence v3.0.
WHO defined daily dose (DDD)
1.8 gram
Not a recommended dose. The DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults. It is a statistical measure used for research and comparison purposes only.
Source: WHO Collaborating Centre for Drug Statistics Methodology, distributed via NHS dm+d BNF mapping files. Contains public sector information licensed under the Open Government Licence v3.0.
Therapeutically similar medicines
Similarity based on WHO Anatomical Therapeutic Chemical (ATC) classification and NHS BNF section grouping. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.
NHS prescribing volume and spending trends
Clinical guidelines and formulary information
British National Formulary
Gabapentin
Source: British National Formulary, NICE. Joint Formulary Committee. Contains public sector information licensed under the Open Government Licence v3.0.
NICE clinical guidance(12)
Multiple sclerosis in adults: management (NG220)
Neuropathic pain in adults: pharmacological management in non-specialist settings (CG173)
Perioperative care in adults (NG180)
Motor neurone disease: assessment and management (NG42)
End of life care for infants, children and young people with life-limiting conditions: planning and management (NG61)
Low back pain and sciatica in over 16s: assessment and management (NG59)
Difelikefalin for treating pruritus in people having haemodialysis (TA890)
Epilepsies in children, young people and adults (NG217)
Restless legs syndrome: Oxycodone/naloxone prolonged release (ESNM67)
Targeted muscle reinnervation for managing limb amputation pain (HTG750)
Headaches in over 12s: diagnosis and management (CG150)
Aptiva for painful diabetic neuropathy (MIB119)
Source: National Institute for Health and Care Excellence (NICE). Contains public sector information licensed under the Open Government Licence v3.0.
Check stock at pharmacies and supply information
Pharmacy stock checkers
Search for this medicine at major UK pharmacy chains. These links open the retailer's own website — results depend on their current online catalogue.
Supply & product information
Official product databases and supply status monitoring
Pharmacy links redirect to the retailer's own search and do not represent real-time stock levels. emc (electronic medicines compendium) is operated by Datapharm Ltd. Shortage information sourced from NHS Specialist Pharmacy Service (SPS), sps.nhs.uk.
Codes for healthcare professionals and prescribing systems
These codes are used by healthcare IT systems and prescribers to identify this medicine.
NHS UK identifiers
Browse tools
SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. BNF codes from NHS Business Services Authority (NHSBSA). ATC codes from the WHO Collaborating Centre for Drug Statistics Methodology (whocc.no).
Active and completed clinical studies from ClinicalTrials.gov
Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.
Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
1 found
Half-life
5-7 hours
Mechanism
The precise mechanism through which gabapentin exerts its therapeutic effects is unclear.
Food interactions
2 warnings
Human targets
8 targets
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
900mg/d
[A186143]…
Half-life
5-7 hours
[L8717][L8720][A186143]…
Protein binding
3%
[L8717][L8720]
Volume of distribution
6 L
[L8717][L8720]…
Metabolism
1%
Elimination
12%
[L8717][L8720]…
Clearance
[L8717][L8720][A186143]…
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
[L8717]
In Europe, gabapentin is indicated for adjunctive therapy in the treatment of partial-onset seizures, with or without secondary generalization, in patients 6 years of age and older and as monotherapy in patients 12 years of age and older. It is also used in adults for the treatment of various types of peripheral neuropathic pain, such as painful diabetic neuropathy.
[L8732]
Known interactions with other medications. Always consult a healthcare professional.
Showing 50 of 822 interactions
[L8765]
Symptoms of overdose are consistent with the drug's adverse effect profile and involve CNS depression (e.g. dizziness, drowsiness, slurred speech, lethargy, loss of consciousness) and gastrointestinal symptoms such as diarrhea.
[L8726][L8720]
Management of overdose should involve symptomatic and supportive treatment. Gabapentin can be removed by hemodialysis - this may be of benefit in some patients, such as those with impaired renal function.
[L8741]
Multi-drug overdoses involving gabapentin, particularly in combination with other CNS depressants such as opioids, can result in coma and death - this possibility should be considered when managing overdosage.
[L8720]
There is some evidence that gabapentin also acts on adenosine receptors[A11009][A186209] and voltage-gated potassium channels,[A186212] though the clinical relevance of its action at these sites is unclear.
Gabapentin is ineffective in absence seizures and should be used in caution in patients with mixed seizure disorders involving absence seizures. Gabapentin has been associated with drug reaction with eosinophilia and systemic symptoms (DRESS), otherwise known as multi-organ hypersensitivity. This reaction can prove fatal and early symptoms such as fever, lymphadenopathy, and rash should be promptly investigated.[L8717][L8720][L8732]
How the body processes this drug — absorption, distribution, metabolism, and elimination
[A186143]
As this process is saturable, the oral bioavailability of gabapentin is inversely proportional to the administered dose - the oral bioavailability of a 900mg/day regimen is approximately 60%, whereas a 4800mg/day regimen results in only 27% bioavailability.
[L8717][L8726]
The Tmax of gabapentin has been estimated to be 2-3 hours.
[L8720][A186143]
Food has no appreciable effect on gabapentin absorption.
[L8717][L8726]
[L8717][L8720][A186143]
In patients with reduced renal function, the elimination t1/2 may be prolonged - in patients with a creatinine clearance of <30 mL/min, the reported half-life of gabapentin was approximately 52 hours.
[L8717][L8720]
[L8717][L8720]
[L8717][L8720]
The drug is found in the CSF in concentrations approximately 9-20% of the corresponding plasma concentrations and is secreted into breast milk in concentrations similar to that seen in plasma.
[L8717][L8720][A186143]
[A186143]
[L8717][L8720]
Cimetidine, an inhibitor of renal tubular secretion, reduces clearance by approximately 12%, suggesting that some degree of tubular secretion is involved in the renal elimination of gabapentin.
[A186143]
[L8717][L8720][A186143]
Proteins and enzymes this drug interacts with in the body
PMID:35293990
Plays an important role in excitation-contraction coupling (By similarity)
PMID:15617512 PMID:18165688 PMID:22660477 PMID:24305054 PMID:9872316 PMID:9872744
Within the heterodimeric GABA receptor, only GABBR1 seems to bind agonists, while GABBR2 mediates coupling to G proteins .
PMID:18165688
Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase .
PMID:10075644 PMID:10773016 PMID:24305054
Signaling inhibits adenylate cyclase, stimulates phospholipase A2, activates potassium channels, inactivates voltage-dependent calcium-channels and modulates inositol phospholipid hydrolysis .
PMID:10075644 PMID:10773016 PMID:10906333 PMID:9872744
Plays a critical role in the fine-tuning of inhibitory synaptic transmission .
PMID:22660477 PMID:9872744
Pre-synaptic GABA receptor inhibits neurotransmitter release by down-regulating high-voltage activated calcium channels, whereas postsynaptic GABA receptor decreases neuronal excitability by activating a prominent inwardly rectifying potassium (Kir) conductance that underlies the late inhibitory postsynaptic potentials .
PMID:10075644 PMID:22660477 PMID:9872316 PMID:9872744
Not only implicated in synaptic inhibition but also in hippocampal long-term potentiation, slow wave sleep, muscle relaxation and antinociception (Probable)
PMID:15617512 PMID:18165688 PMID:22660477 PMID:24305054 PMID:36103875 PMID:9872316 PMID:9872744
Within the heterodimeric GABA receptor, only GABBR1 seems to bind agonists, while GABBR2 mediates coupling to G proteins .
PMID:18165688
Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase .
PMID:10075644 PMID:10773016 PMID:10906333 PMID:24305054 PMID:9872744
Signaling inhibits adenylate cyclase, stimulates phospholipase A2, activates potassium channels, inactivates voltage-dependent calcium-channels and modulates inositol phospholipid hydrolysis .
PMID:10075644
Calcium is required for high affinity binding to GABA (By similarity). Plays a critical role in the fine-tuning of inhibitory synaptic transmission .
PMID:9844003
Pre-synaptic GABA receptor inhibits neurotransmitter release by down-regulating high-voltage activated calcium channels, whereas postsynaptic GABA receptor decreases neuronal excitability by activating a prominent inwardly rectifying potassium (Kir) conductance that underlies the late inhibitory postsynaptic potentials .
PMID:10075644 PMID:22660477 PMID:9844003 PMID:9872316 PMID:9872744
Not only implicated in synaptic inhibition but also in hippocampal long-term potentiation, slow wave sleep, muscle relaxation and antinociception (Probable). Activated by (-)-baclofen, cgp27492 and blocked by phaclofen PMID:24305054 PMID:9844003 PMID:9872316
PMID:15111129 PMID:23339110
Overexpression induces apoptosis
They are involved in pain signaling .
PMID:25296916
Calcium channels containing alpha-1B subunit may play a role in directed migration of immature neurons. Mediates Ca(2+) release probability at hippocampal neuronal soma and synaptic terminals (By similarity)
Enzymes involved in drug metabolism — important for understanding drug interactions
Proteins that transport this drug across cell membranes
PMID:10049700 PMID:10574970 PMID:11557028 PMID:11564694 PMID:12117417 PMID:12225859 PMID:15769744 PMID:18262359 PMID:25998567 PMID:30867591 PMID:9751058
The heterodimer with SLC3A2 mediates the uptake of L-DOPA (By similarity). Functions as an amino acid exchanger .
PMID:11557028 PMID:12117417 PMID:12225859 PMID:30867591
May play a role in the transport of L-DOPA across the blood-brain barrier (By similarity). May act as the major transporter of tyrosine in fibroblasts (Probable).
May mediate blood-to-retina L-leucine transport across the inner blood-retinal barrier (By similarity). Can mediate the transport of thyroid hormones diiodothyronine (T2), triiodothyronine (T3) and thyroxine (T4) across the cell membrane .
PMID:11564694
When associated with LAPTM4B, the heterodimer formed by SLC3A2 and SLC7A5 is recruited to lysosomes to promote leucine uptake into these organelles, and thereby mediates mTORC1 activation .
PMID:25998567
Involved in the uptake of toxic methylmercury (MeHg) when administered as the L-cysteine or D,L-homocysteine complexes .
PMID:12117417
Involved in the cellular activity of small molecular weight nitrosothiols, via the stereoselective transport of L-nitrosocysteine (L-CNSO) across the membrane PMID:15769744
ATC N02BF01
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
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Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Gabapentin
Additional database identifiers
Drugs Product Database (DPD)
470
ChemSpider
3328
BindingDB
50080153
PDB
GBN
ZINC
ZINC000000004949
HUGO Gene Nomenclature Committee (HGNC)
HGNC:1399
GenAtlas
CACNA2D1
GeneCards
CACNA2D1
GenBank Gene Database
M76559
GenBank Protein Database
179762
UniProt Accession
CA2D1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4507
GenAtlas
GABBR2
GeneCards
GABBR2
GenBank Gene Database
AJ012188
GenBank Protein Database
3776098
Guide to Pharmacology
241
UniProt Accession
GABR2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4070
GenAtlas
GABBR1
GeneCards
GABBR1
GenBank Gene Database
AJ225028
GenBank Protein Database
3892594
Guide to Pharmacology
240
UniProt Accession
GABR1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:1400
GenAtlas
CACNA2D2
GeneCards
CACNA2D2
GenBank Gene Database
AJ251368
UniProt Accession
CA2D2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:1399
GenAtlas
CACNA2D1
GeneCards
CACNA2D1
GenBank Gene Database
M76559
GenBank Protein Database
179762
UniProt Accession
CA2D1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:1400
GenAtlas
CACNA2D2
GeneCards
CACNA2D2
GenBank Gene Database
AJ251368
UniProt Accession
CA2D2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:1389
GenAtlas
CACNA1B
GeneCards
CACNA1B
GenBank Gene Database
M94172
GenBank Protein Database
179758
Guide to Pharmacology
533
UniProt Accession
CAC1B_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:262
GenAtlas
ADORA1
GeneCards
ADORA1
GenBank Gene Database
S45235
GenBank Protein Database
256155
Guide to Pharmacology
18
UniProt Accession
AA1R_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:6297
GenAtlas
KCNQ3
GeneCards
KCNQ3
GenBank Gene Database
AF071491
Guide to Pharmacology
562
UniProt Accession
KCNQ3_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:6299
GenAtlas
KCNQ5
GeneCards
KCNQ5
GenBank Gene Database
AF249278
Guide to Pharmacology
564
UniProt Accession
KCNQ5_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:976
GenAtlas
BCAT1
GeneCards
BCAT1
GenBank Gene Database
U21551
GenBank Protein Database
1036780
Guide to Pharmacology
3210
UniProt Accession
BCAT1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11063
GenAtlas
SLC7A5
GeneCards
SLC7A5
GenBank Gene Database
AF077866
GenBank Protein Database
3639058
UniProt Accession
LAT1_HUMAN
International reference pricing
Reference pricing from DrugBank. Prices are indicative and may not reflect current UK costs.
Source: DrugBank. Used under CC BY-NC 4.0 academic licence for non-commercial purposes.
Patent information
All patents expired, 13 expired
Source: DrugBank · CC BY-NC 4.0. Patent data sourced from national patent offices. Expiry dates may not reflect extensions, regulatory exclusivity periods, or legal challenges.
DrugBank citations
If you use DrugBank data in your research, please cite the following publications: