Two medicines, side by side
Tiagabine vs gabapentin
Tiagabine and gabapentin are both labeled for seizures and epilepsy. Drugs@FDA records approvals of tiagabine since 1997 and of gabapentin since 1993. Pharmacies paid $2.62 per tiagabine HCl 2 mg tablet and $0.0218 per gabapentin 100 mg capsule (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. How each works, in its label's words: Tiagabine, “Mechanism of Action The precise mechanism by which tiagabine exerts its antiseizure effect is unknown, although it is believed to be related to its ability, documented in in vitro experiments, to …”; Gabapentin, “The precise mechanisms by which gabapentin produces its analgesic and antiepileptic actions are unknown.”
Check it at the source: the tiagabine FDA label on DailyMed (effective September 30, 2021); the gabapentin FDA label on DailyMed (effective May 12, 2026).
Highlights of the tiagabine record
Tiagabine (Gabitril) · label of September 30, 2021
Used for
From the label: indicationsTiagabine HCl is indicated as adjunctive therapy in adults and children 12 years and older in the treatment of partial seizures.
On the market
- Earliest approval on file
- September 30, 1997
- Generic labelers
- 2 labelers
- Pharmacy cost
- $2.62 per tablet
Supply and safety
- Shortage
- A presentation being discontinued
- Recalls
- 1
Highlights of the gabapentin record
Gabapentin (Neurontin) · label of May 12, 2026
Used for
From the label: indicationsNEURONTIN ® is indicated for: • Management of postherpetic neuralgia in adults • Adjunctive therapy in the treatment of partial onset seizures, with and without secondary generalization, in adults and pediatric patients 3 years and older with epilepsy NEURONTIN is indicated for: • Postherpetic neuralgia in adults ( 1 ) • Adjunctive therapy in the treatment of partial onset seizures, with and without secondary generalization, in adults and pediatric patients 3 years and older with epilepsy […]
On the market
- Earliest approval on file
- December 30, 1993
- Generic labelers
- 85 labelers
- Pharmacy cost
- $0.0218 per capsule
Supply and safety
- Shortage
- No current entry
- Recalls
- 22
Source: FDA drug labels via openFDA (Tiagabine label of September 30, 2021, Gabapentin label of May 12, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do tiagabine and gabapentin differ on the record?
How each works, in its label's words: Tiagabine, “Mechanism of Action The precise mechanism by which tiagabine exerts its antiseizure effect is unknown, although it is believed to be related to its ability, documented in in vitro experiments, to …”; Gabapentin, “The precise mechanisms by which gabapentin produces its analgesic and antiepileptic actions are unknown.”
Both are in FDA's class anti-epileptic agents.
Half-life, in each label's words: Tiagabine, “The elimination half-life of tiagabine is 7 to 9 hours in normal volunteers.”; Gabapentin, “Gabapentin elimination half-life is 5 to 7 hours and is unaltered by dose or following multiple dosing.”
Generics: tiagabine since 2011; gabapentin since 2003 (Drugs@FDA).
| Tiagabine | Gabapentin | |
|---|---|---|
| Labeled for | Seizures and epilepsy | Nerve pain and fibromyalgia, Seizures and epilepsy |
| Pharmacologic class | Anti-epileptic Agent | Anti-epileptic Agent |
| How it works (label) | Mechanism of Action The precise mechanism by which tiagabine exerts its antiseizure effect is unknown, although it is believed to be related to its ability, documented in in vitro experiments, to enhance the activity of gamma aminobutyric … | The precise mechanisms by which gabapentin produces its analgesic and antiepileptic actions are unknown. |
| Half-life (label) | The elimination half-life of tiagabine is 7 to 9 hours in normal volunteers. | Gabapentin elimination half-life is 5 to 7 hours and is unaltered by dose or following multiple dosing. |
| Earliest approval on file (Drugs@FDA) | September 30, 1997 | December 30, 1993 |
| First generic approved | November 4, 2011 | September 12, 2003 |
| Generic labelers (NDC) | 2 labelers | 85 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $2.62 per tablet (Tiagabine HCl 2 mg tablet) | $0.0218 per capsule (Gabapentin 100 mg capsule) |
| 12-month price change | +25% | +0.9% |
| Boxed warning | No | No |
| Shortage now | A presentation being discontinued | No current entry |
| Recalls recorded | 1 | 22 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 84 | 362,654 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
Do their labels mention each other?
Tiagabine label, drug interactionsCarbamazepine, phenytoin, primidone, and phenobarbital are generally classified as enzyme inducers; valproate and gabapentin are not.
Source: FDA drug labels via openFDA
What next?
- Alternatives to tiagabine
- every medicine labeled for the same conditions