Head-to-head comparisons of medication uses, side effects, warnings, and more.
Key takeaways
Phenytoin (Dilantin) and lamotrigine (Lamictal) are both antiepileptic medications used to treat seizures, but they have some key differences. Phenytoin is specifically used for tonic-clonic and psychomotor seizures, as well as seizures related to brain surgery. Lamotrigine, on the other hand, can treat partial and tonic-clonic seizures, seizures of Lennox-Gastaut syndrome, and bipolar disorder. Phenytoin requires regular blood tests to monitor levels and has a risk of serious side effects like liver damage and severe allergic reactions, especially in people of Asian ancestry with the HLA-B*1502 gene. Lamotrigine also has serious risks, including severe skin reactions and meningitis. Its dose must be increased slowly to avoid the risk of serious rash. Both medications interact with many other drugs, including prescribed and over-the-counter medications. Phenytoin is available in capsules, chewable tablets, liquid, and injection, while lamotrigine in chewable and quick-dissolving tablets, as well as extended-release tablets.
Phenytoin (Dilantin)
Lamotrigine (Lamictal)
Phenytoin (Dilantin)
Lamotrigine (Lamictal)
Summary of Dilantin vs. Lamictal
Summary for Antiepileptic
Prescription only
Phenytoin (Dilantin) is an antiepileptic medication used to treat and prevent seizures in adults and children. It comes in a capsule, chewable tablet, and liquid suspension that you take by mouth. The dose depends on your age, weight, and how well your seizures are controlled. Common side effects include trouble with coordination, unpredictable eye movements, and sleepiness. You’ll need regular blood tests to avoid toxicity, which is when the amount of medication in your body is too high and could be dangerous.
Summary for Antiepileptic
Prescription only
Lamotrigine (Lamictal) can be used alone or together with other medications to treat seizures. It's available in immediate-release and extended-release formulations. The immediate-release formulation can also be used for bipolar disorder. Lamotrigine (Lamictal) can cause serious skin reactions like rash.
•Unknown if safe or works well in children under 2 years old (immediate release) or children under 13 years old (extended release)
Common Side Effects of Dilantin vs. Lamictal
Common Side Effects for
•Unpredictable eye movements
•Trouble with coordination
•Slurred speech
•Sleepiness
•Confusion
Common Side Effects for
Below are common side effects reported by adults who took this medication along with other treatments. Percentages can differ depending on your condition (e.g., bipolar) and your age.