Anticonvulsant drugs are classified as either first-generation (classic) agents or second-generation agents. Second-generation anticonvulsants are usually better tolerated and have a broader therapeutic range than classic anticonvulsant drugs. The choice of drug is guided by the type of seizure. First-line treatment for focal seizures includes, e.g., lamotrigine or levetiracetam, while valproate is used for generalized seizures. While all anticonvulsants have dose-dependent side effects on the central nervous system (e.g., somnolence, nausea), select agents also have other side effects (e.g., gingival hyperplasia caused by phenytoin). Anticonvulsants are also used for pain management (e.g., carbamazepine or gabapentin) and as mood stabilizers in bipolar disorders (valproate).
For more information on the treatment of generalized seizures, see .
Anticonvulsant drugs inhibit neural activity (↓ neural excitation, ↑ neural inhibition) and increase the seizure threshold by interacting with specific receptors and ion channels.
|Overview of anticonvulsant drugs|
|Classification||Agent||Indication||Mechanism of action||Side effects|
First-generation (classic) anticonvulsants
|Second-generation (newer) anticonvulsants|| |
|Pregabalin (tentative FDA approval)|
You can use the following to remember the features of PHENYTOIN: cytochrome P-450 interaction, Hirsutism, Enlarged gums (gingival hyperplasia), Nystagmus, Yellow-browning of skin (melasma), Teratogenicity, Osteomalacia, Interacts with folate, Neuropathy
To remember that the most important side effects of ethoSUXimide are Steven-Johnson syndrome, fatigue, headache, ABdominal upset, and ALLErGies (e.g., urticaria), think of “It sucks that Steven's FATher has given everyone a headache with his ABsurd ALLEGorizations.”
To remember a crucial side effect of vigabatrin, think of “Vision goes away by accident.”
To remember that phenobarbital is first-line treatment for neonates, think of “Phenobarbital is phenomenal for treating babies.”
To remember that the most common side effects of topiramate are speech impairment, weight loss (light), cognitive impairment, sedation, and kidney stones, think of “It leaves you speechless how lightly the cog railway travels through sediments and stones to the top.”
- Monotherapy should always be the first-line treatment: increase the dosage of the drug to the therapeutic range before initiating combination therapy
- Combination therapy: drugs from different classes and/or with different pharmacologic modes of action for refractory seizures 
- For more detailed approaches to seizure treatment and epilepsy, see .
Special patient groups
- Classic anticonvulsants (especially carbamazepine and sodium valproate!) should be avoided if possible → teratogenic effects
- Newer anticonvulsants: lack of medical data and trials during pregnancy
- The choice of treatment depends on the type of seizure and which substance enables optimal control of seizures.