TABLE 5.

Common and serious adverse effects of selected antiseizure drugs

Antiseizure drug	Systemic adverse effects	Neurologic adverse effects	Rare idiosyncratic reactions
Brivaracetam	Nausea, vomiting, constipation, fatigue	Headache, somnolence, dizziness, abnormal coordination, nystagmus, mood changes
Carbamazepine	Nausea, vomiting, diarrhea, a plastic anemia, leukopenia, hyponatremia (common reason for discontinuation), hepatotoxicity, rash, pruritus	Ataxia, dizziness, blurred vision, diplopia, headache	Erythematous maculopapular rash (Steven‐Johnson syndrome and toxic epidermal necrolysis), teratogenicity
Cenobamate	Nausea, vomiting, fatigue, hyperkalemia, QT shortening	Somnolence, dizziness, headache, balance disorder, diplopia	Drug reaction with eosinophilia and systemic symptoms (DRESS)/multiorgan hypersensitivity (at high doses)
Eslicarbazepine	Nausea, vomiting, diarrhea, hyponatremia, rash	Dizziness, drowsiness, headache, somnolence, diplopia, ataxia, blurred vision, tremor
Ethosuximide	Nausea, vomiting	Sleep disturbance, drowsiness, hyperactivity
Felbamate	Nausea, vomiting, anorexia, weight loss	Insomnia, dizziness, headache, ataxia	Aplastic anemia, severe hepatitis/hepatic failure
Gabapentin	Infrequent	Somnolence, dizziness, ataxia, headache, tremor, and fatigue
Lacosamide	Nausea, vomiting, increased cardiac conduction (PR interval)	Dizziness, ataxia, diplopia, headache
Lamotrigine	Nausea, rash, cardiac arrhythmias	Dizziness, tremor, diplopia	Steven‐Johnson syndrome
Levetiracetam	Fatigue, infection, anemia, leukopenia	Somnolence, dizziness, agitation, anxiety, irritability, depression, psychosis
Oxcarbazepine	Nausea, rash, hyponatremia (more common)	Somnolence, headache, dizziness, vertigo, ataxia, diplopia
Perampanel	Weight gain, fatigue, nausea	Dizziness, somnolence, irritability, gait disturbance, falls (with high dose), aggression, mood alteration
Phenobarbital	Nausea, rash	Somnolence, ataxia, dizziness, confusion, cognitive dysfunction, tolerance, dependence
Phenytoin	Gingival hyperplasia, hirsutism, megaloblastic anemia, peripheral neuropathy, osteoporosis, rash	Nystagmus (early sign of phenytoin administration), diplopia, ataxia, somnolence
Pregabalin	Weight gain, peripheral edema, dry mouth	Somnolence, dizziness, ataxia, headache, and tremor
Rufinamide	Nausea, vomiting, leukopenia, cardiac conduction (QT interval shortening)	Somnolence, fatigue, dizziness, ataxia, headache, diplopia
Tiagabine	Abdominal pain, nausea, lack of energy	Dizziness, difficulty concentrating, somnolence, nervousness, tremor, language problems
Topiramate	Anorexia, weight loss, paresthesia, fatigue	Nervousness, psychomotor slowing, language problems, depression, anxiety, mood problems, tremor	Acute glaucoma (may require prompt drug withdrawal).
Valproate	Gastrointestinal irritation, weight gain, hair loss, easy bruising	Ataxia, somnolence, tremor	Hepatotoxicity, teratogenicity, and thrombocytopenia
Vigabatrin	Fatigue	Somnolence, headache, dizziness, agitation, confusion, psychosis.	Irreversible bilateral concentric visual field defect
Zonisamide	Weight loss, nausea, anorexia	Somnolence, dizziness, confusion, headache, psychosis	Potentially serious skin rashes