Two medicines, side by side
Carbamazepine vs lamotrigine
Carbamazepine and lamotrigine are both labeled for bipolar disorder and seizures and epilepsy. Drugs@FDA records approvals of carbamazepine since 1968 and of lamotrigine since 1994. Pharmacies paid $0.119 per carbamazepine 200 mg tablet and $0.0268 per lamotrigine 25 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. Lamotrigine's other strengths are brand-only: $2.86 per mL (Subvenite 10 mg/mL suspension). How each works, in its label's words: Carbamazepine, “It appears to act by reducing polysynaptic responses and blocking the post-tetanic potentiation.”; Lamotrigine, “The precise mechanism(s) by which lamotrigine exerts its anticonvulsant action are unknown.”
Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026); the lamotrigine FDA label on DailyMed (effective October 10, 2025).
Highlights of the carbamazepine record
Carbamazepine (Tegretol) · label of August 20, 2026
SERIOUS DERMATOLOGIC REACTIONS AND HLA-B*1502 ALLELE SERIOUS AND SOMETIMES FATAL DERMATOLOGIC REACTIONS, INCLUDING TOXIC EPIDERMAL NECROLYSIS (TEN) AND STEVENS-JOHNSON SYNDROME (SJS), HAVE BEEN REPORTED DURING TREATMENT WITH TEGRETOL. THESE REACTIONS ARE ESTIMATED TO OCCUR IN 1 TO 6 PER 10,000 NEW USERS IN COUNTRIES WITH MAINLY CAUCASIAN POPULATIONS, BUT THE RISK IN SOME ASIAN COUNTRIES IS ESTIMATED TO BE ABOUT 10 TIMES HIGHER.
Used for
From the label: indicationsEpilepsy Tegretol is indicated for use as an anticonvulsant drug. Evidence supporting efficacy of Tegretol as an anticonvulsant was derived from active drug-controlled studies that enrolled patients with the following seizure types: Partial seizures with complex symptomatology (psychomotor, temporal lobe). Patients with these seizures appear to show greater improvement than those with other types. […]
On the market
- Earliest approval on file
- March 11, 1968
- Generic labelers
- 42 labelers
- Pharmacy cost
- $0.119 per tablet
Supply and safety
- Shortage
- A presentation being discontinued
- Recalls
- 11
Highlights of the lamotrigine record
Lamotrigine (Lamictal) · label of October 10, 2025
SERIOUS SKIN RASHES LAMICTAL can cause serious rashes requiring hospitalization and discontinuation of treatment. The incidence of these rashes, which have included Stevens-Johnson syndrome, is approximately 0.3% to 0.8% in pediatric patients (aged 2 to 17 years) and 0.08% to 0.3% in adults receiving LAMICTAL. One rash-related death was reported in a prospectively followed cohort of 1,983 pediatric patients (aged 2 to 16 years) with epilepsy taking LAMICTAL as adjunctive therapy.
Used for
From the label: indicationsLAMICTAL is indicated for: Epilepsy–adjunctive therapy in patients aged 2 years and older: • partial-onset seizures. • primary generalized tonic-clonic (PGTC) seizures. • generalized seizures of Lennox-Gastaut syndrome. […]
On the market
- Earliest approval on file
- December 27, 1994
- Generic labelers
- 49 labelers
- Pharmacy cost
- $0.0268 per tablet
Supply and safety
- Shortage
- A presentation being discontinued
- Recalls
- 10
Source: FDA drug labels via openFDA (Carbamazepine label of August 20, 2026, Lamotrigine label of October 10, 2025); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do carbamazepine and lamotrigine differ on the record?
How each works, in its label's words: Carbamazepine, “It appears to act by reducing polysynaptic responses and blocking the post-tetanic potentiation.”; Lamotrigine, “The precise mechanism(s) by which lamotrigine exerts its anticonvulsant action are unknown.”
Both are in FDA's class mood stabilizers.
Both labels carry a boxed warning; the records quote them.
Generics: carbamazepine since 1986; lamotrigine since 2006 (Drugs@FDA).
| Carbamazepine | Lamotrigine | |
|---|---|---|
| Labeled for | Bipolar disorder, Seizures and epilepsy | Seizures and epilepsy, Bipolar disorder |
| Pharmacologic class | Mood Stabilizer | Anti-epileptic Agent, Mood Stabilizer |
| How it works (label) | Mechanism of Action Tegretol has demonstrated anticonvulsant properties in rats and mice with electrically and chemically induced seizures. It appears to act by reducing polysynaptic responses and blocking the post-tetanic potentiation. | The precise mechanism(s) by which lamotrigine exerts its anticonvulsant action are unknown. |
| Half-life (label) | Initial half-life values range from 25 to 65 hours, decreasing to 12 to 17 hours on repeated doses. | n/a |
| Earliest approval on file (Drugs@FDA) | March 11, 1968 | December 27, 1994 |
| First generic approved | August 14, 1986 | June 21, 2006 |
| Generic labelers (NDC) | 42 labelers | 49 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.119 per tablet (Carbamazepine 200 mg tablet) | $0.0268 per tablet (Lamotrigine 25 mg tablet) |
| 12-month price change | +0.6% | -12% |
| Boxed warning | Yes | Yes |
| Shortage now | A presentation being discontinued | A presentation being discontinued |
| Recalls recorded | 11 | 10 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 66,615 | 130,994 |
| 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?
Carbamazepine label, drug interactions… dihydropyridine calcium channel blockers (e.g., felodipine), doxycycline, eslicarbazepine, ethosuximide, everolimus, haloperidol, imatinib, itraconazole, lamotrigine, levothyroxine, methadone, methsuximide, mianserin, midazolam, olanzapine, oral and other hormonal contraceptives, oxcarbazepine, paliperidone, phensuximide, phenytoin, praziquantel, protease inhibitors, risperidone, sertraline, sirolimus, tadalafil …
Carbamazepine label, drug interactions… blockers (e.g., felodipine), doxycycline, edoxaban (6), eslicarbazepine, ethosuximide, everolimus, felbamate, haloperidol, imatinib, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, methsuximide, midazolam, mirtazapine, nefazodone, nortriptyline, olanzapine, oral and other hormonal contraceptives (2), oxcarbazepine, paliperidone, phenytoin (3), praziquantel, protease inhibitors, quetiapine …
Lamotrigine label, drug interactionsConcomitant Drug: Carbamazepine and carbamazepine epoxide; Effect on Concentration of Lamotrigine or Concomitant Drug: ↓ lamotrigine ? carbamazepine epoxide; Clinical Comment: Addition of carbamazepine decreases lamotrigine concentration approximately 40%. May increase carbamazepine epoxide levels.
Lamotrigine label, drug interactionsConcomitant Drug: Carbamazepine and carbamazepine epoxide; Effect on Concentration of Lamotrigine or Concomitant Drug: ↓ lamotrigine; Clinical Comment: Addition of carbamazepine decreases lamotrigine concentration approximately 40%.
Source: FDA drug labels via openFDA
What next?
- Alternatives to carbamazepine
- every medicine labeled for the same conditions