Lamotrigine vs Carbamazepine: side effects in FDA adverse event reports
At a glance
| Lamotrigine | Carbamazepine | |
|---|---|---|
| Drug class | Anti-epileptic Agent, Mood Stabilizer | Mood Stabilizer |
| Brand names | – | – |
| FAERS reports | 130,963 | 66,609 |
| Serious | 72% | 86% |
| Death outcome | 11,279 | 5,605 |
| Boxed warning | Yes SERIOUS SKIN RASHES Lamotrigine can cause serious rashes requiring hospitalization and discontinuation of treatment. The incidence of these rashes, which have i | Yes SERIOUS DERMATOLOGIC REACTIONS AND HLA-B*1502 ALLELE SERIOUS AND SOMETIMES FATAL DERMATOLOGIC REACTIONS, INCLUDING TOXIC EPIDERMAL NECROLYSIS (TEN) AND STEVENS- |
Signals both drugs share
| Reaction | Lamotrigine | Carbamazepine | Label screen (A / B) |
|---|---|---|---|
| Epilepsy | 3,415 · PRR 20.1 | 2,022 · PRR 22.3 | Labeled — boxed warning / Likely indication confounding |
| Petit mal epilepsy | 696 · PRR 25.3 | 431 · PRR 29.1 | Labeled (related wording) / Likely indication confounding |
| Complex partial seizures | 173 · PRR 28.9 | 160 · PRR 52.0 | Labeled (related wording) / Likely indication confounding |
| Simple partial seizures | 82 · PRR 17.8 | 65 · PRR 27.2 | Labeled (related wording) / Likely indication confounding |
| Change in seizure presentation | 86 · PRR 24.0 | 47 · PRR 24.2 | Labeled (related wording) / Likely indication confounding |
| Partial seizures with secondary generalisation | 81 · PRR 33.3 | 46 · PRR 34.2 | Labeled (related wording) / Likely indication confounding |
| Partial seizures | 548 · PRR 18.9 | 390 · PRR 25.7 | Likely indication confounding / Likely indication confounding |
| Aura | 280 · PRR 28.2 | 135 · PRR 24.6 | Not in label — unassessed / Not in label — unassessed |
| Myoclonic epilepsy | 210 · PRR 26.5 | 125 · PRR 29.1 | Likely indication confounding / Likely indication confounding |
| Lip erosion | 225 · PRR 70.4 | 64 · PRR 29.9 | Not in label — unassessed / Not in label — unassessed |
| Focal dyscognitive seizures | 181 · PRR 30.0 | 102 · PRR 30.8 | Likely indication confounding / Likely indication confounding |
| Sudden unexplained death in epilepsy | 170 · PRR 73.3 | 78 · PRR 53.0 | Likely indication confounding / Likely indication confounding |
| Atonic seizures | 114 · PRR 26.6 | 58 · PRR 24.6 | Likely indication confounding / Likely indication confounding |
Labeled signals distinctive to Lamotrigine
- Stevens-johnson syndrome — n=2,615, PRR 21.2 Labeled — boxed warning
- Duodenal ulcer perforation — n=824, PRR 20.1 Labeled (related wording)
- Peripheral venous disease — n=638, PRR 30.3 Labeled (related wording)
- Seizure cluster — n=92, PRR 20.6 Labeled adverse reaction
Labeled signals distinctive to Carbamazepine
- Drug rash with eosinophilia and systemic symptoms — n=446, PRR 49.3 Labeled (related wording)
- Asthma-chronic obstructive pulmonary disease overlap syndrome — n=101, PRR 75.7 Labeled (related wording)
Common questions
Which has more reported side effects, Lamotrigine or Carbamazepine?
Lamotrigine has 130,963 FAERS reports and Carbamazepine 66,609. More reports does not mean more dangerous: volume follows how widely and how long a drug has been used, prescription vs over-the-counter status, and publicity. The seriousness share (72% vs 86%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Lamotrigine and Carbamazepine share?
Both drugs carry disproportionality signals for epilepsy, petit mal epilepsy, complex partial seizures, simple partial seizures, change in seizure presentation. Shared signals often reflect a shared drug class or the condition both are used for.
Is Lamotrigine or Carbamazepine safer?
FAERS cannot answer that: it has no denominator and no comparator. Use this page to see which risks are already on each label and which signals are unlabeled, then check the prescribing information and your clinician for your situation.
Sources: openFDA FAERS pair statistics (OpenPV build 2026-09-14), FDA labels via openFDA, openFDA count queries for seriousness and deaths. Pair chosen because it is a commonly searched comparison. Generated 2026-10-08.