Adults: In adults experiencing partial onset seizures, levetiracetam use is associated with the occurrence of central nervous system adverse events that can be classified into the following categories: 1) somnolence and fatigue, 2) coordination difficulties, and 3) behavioral abnormalities.
In controlled trials of adult patients with epilepsy experiencing partial onset seizures, 14.8% of levetiracetam-treated patients reported somnolence, compared to 8.4% of placebo patients. There was no clear dose response up to 3000 mg/day. In a study where there was no titration, about 45% of patients receiving 4000 mg/day reported somnolence. The somnolence was considered serious in 0.3% of the treated patients, compared to 0% in the placebo group. About 3% of levetiracetam-treated patients discontinued treatment due to somnolence, compared to 0.7% of placebo patients. In 1.4% of treated patients and in 0.9% of placebo patients the dose was reduced, while 0.3% of the treated patients were hospitalized due to somnolence.
In controlled trials of adult patients with epilepsy experiencing partial onset seizures, 14.7% of treated patients reported asthenia, compared to 9.1% of placebo patients. Treatment was discontinued in 0.8% of treated patients as compared to 0.5% of placebo patients. In 0.5% of treated patients and in 0.2% of placebo patients the dose was reduced.
A total of 3.4% of levetiracetam-treated patients experienced coordination difficulties, (reported as either ataxia, abnormal gait, or incoordination) compared to 1.6% of placebo patients. A total of 0.4% of patients in controlled trials discontinued levetiracetam treatment due to ataxia, compared to 0% of placebo patients. In 0.7% of treated patients and in 0.2% of placebo patients the dose was reduced due to coordination difficulties, while one of the treated patients was hospitalized due to worsening of pre-existing ataxia.
Somnolence, asthenia and coordination difficulties occurred most frequently within the first 4 weeks of treatment.
In controlled trials of patients with epilepsy experiencing partial onset seizures, 5 (0.7%) of levetiracetam-treated patients experienced psychotic symptoms compared to 1 (0.2%) placebo patient. Two (0.3%) levetiracetam-treated patients were hospitalized and their treatment was discontinued. Both events, reported as psychosis, developed within the first week of treatment and resolved within 1 to 2 weeks following treatment discontinuation. Two other events, reported as hallucinations, occurred after 1 to 5 months and resolved within 2 to 7 days while the patients remained on treatment. In one patient experiencing psychotic depression occurring within a month, symptoms resolved within 45 days while the patient continued treatment. A total of 13.3% of levetiracetam patients experienced other behavioral symptoms (reported as aggression, agitation, anger, anxiety, apathy, depersonalization, depression, emotional lability, hostility, irritability, etc.) compared to 6.2% of placebo patients. Approximately half of these patients reported these events within the first 4 weeks. A total of 1.7% of treated patients discontinued treatment due to these events, compared to 0.2% of placebo patients. The treatment dose was reduced in 0.8% of treated patients and in 0.5% of placebo patients. A total of 0.8% of treated patients had a serious behavioral event (compared to 0.2% of placebo patients) and were hospitalized.
Pediatric Patients: In pediatric patients experiencing partial onset seizures, levetiracetam is associated with somnolence, fatigue, and behavioral abnormalities.
In the double-blind, controlled trial in children with epilepsy experiencing partial onset seizures, 22.8% of levetiracetam-treated patients experienced somnolence, compared to 11.3% of placebo patients. The design of the study prevented accurately assessing dose-response effects. No patient discontinued treatment for somnolence. In about 3% of levetiracetam-treated patients and in 3.1% of placebo patients the dose was reduced as a result of somnolence.
Asthenia was reported in 8.9% of levetiracetam-treated patients, compared to 3.1% of placebo patients. No patient discontinued treatment for asthenia, but asthenia led to a dose reduction in 3% of levetiracetam-treated patients compared to 0% of placebo patients.
A total of 37.6% of the levetiracetam-treated patients experienced behavioral symptoms (reported as agitation, anxiety, apathy, depersonalization, depression, emotional lability, hostility, hyperkinesia, nervousness, neurosis, and personality disorder), compared to 18.6% of placebo patients. Hostility was reported in 11.9% of levetiracetam-treated patients, compared to 6.2% of placebo patients. Nervousness was reported in 9.9% of levetiracetam-treated patients, compared to 2.1% of placebo patients. Depression was reported in 3% of levetiracetam-treated patients, compared to 1% of placebo patients.
A total of 3% of levetiracetam-treated patients discontinued treatment due to psychotic and nonpsychotic adverse events, compared to 4.1% of placebo patients. Overall, 10.9% of levetiracetam-treated patients experienced behavioral symptoms associated with discontinuation or dose reduction, compared to 6.2% of placebo patients.
In well-controlled clinical studies in adults with partial onset seizures, the most frequently reported adverse events associated with the use of levetiracetam in combination with other AEDs, not seen at an equivalent frequency among placebo-treated patients, were somnolence, asthenia, infection and dizziness. In the well-controlled pediatric clinical study in children 4 to 16 years of age with partial onset seizures, the adverse events most frequently reported with the use of levetiracetam in combination with other AEDs, not seen at an equivalent frequency among placebo-treated patients, were somnolence, accidental injury, hostility, nervousness, and asthenia.
Table 8 lists treatment-emergent adverse events that occurred in at least 1% of adult epilepsy patients treated with levetiracetam participating in placebo-controlled studies and were numerically more common than in patients treated with placebo. Table 9 lists treatment-emergent adverse events that occurred in at least 2% of pediatric epilepsy patients (ages 4 to 16 years) treated with levetiracetam participating in the placebo-controlled study and were numerically more common than in pediatric patients treated with placebo. In these studies, either levetiracetam or placebo was added to concurrent AED therapy. Adverse events were usually mild to moderate in intensity.
Table 8: Incidence (%) Of Treatment-Emergent Adverse Events In Placebo-Controlled, Add-On Studies In Adults Experiencing Partial Onset Seizures By Body System (Adverse Events Occurred In At Least 1% Of Levetiracetam-Treated Patients And Occurred More Frequently Than Placebo-Treated Patients)Body System/ Adverse Event | Levetiracetam (N=769) % | Placebo (N=439) % |
| Body as a Whole | | |
| Asthenia | 15 | 9 |
| Headache | 14 | 13 |
| Infection | 13 | 8 |
| Pain | 7 | 6 |
| Digestive System | | |
| Anorexia | 3 | 2 |
| Nervous System | | |
| Somnolence | 15 | 8 |
| Dizziness | 9 | 4 |
| Depression | 4 | 2 |
| Nervousness | 4 | 2 |
| Ataxia | 3 | 1 |
| Vertigo | 3 | 1 |
| Amnesia | 2 | 1 |
| Anxiety | 2 | 1 |
| Hostility | 2 | 1 |
| Paresthesia | 2 | 1 |
| Emotional Lability | 2 | 0 |
| Respiratory System | | |
| Pharyngitis | 6 | 4 |
| Rhinitis | 4 | 3 |
| Cough Increased | 2 | 1 |
| Sinusitis | 2 | 1 |
| Special Senses | | |
| Diplopia | 2 | 1 |
Other events reported by at least 1% of adult levetiracetam-treated patients but as or more frequent in the placebo group were the following: abdominal pain, accidental injury, amblyopia, arthralgia, back pain, bronchitis, chest pain, confusion, constipation, convulsion, diarrhea, drug level increased, dyspepsia, ecchymosis, fever, flu syndrome, fungal infection, gastroenteritis, gingivitis, grand mal convulsion, insomnia, nausea, otitis media, rash, thinking abnormal, tremor, urinary tract infection, vomiting and weight gain.
Table 9: Incidence (%) Of Treatment-Emergent Adverse Events In A Placebo-Controlled, Add-On Study In Pediatric Patients Ages 4 To 16 Years Experiencing Partial Onset Seizures By Body System (Adverse Events Occurred In At Least 2% Of Levetiracetam-Treated Patients And Occurred More Frequently Than Placebo-Treated Patients)Body System/ Adverse Event | Levetiracetam (N=101) % | Placebo (N=97) % |
| Body as a Whole | | |
| Accidental Injury | 17 | 10 |
| Asthenia | 9 | 3 |
| Pain | 6 | 3 |
| Flu Syndrome | 3 | 2 |
| Face Edema | 2 | 1 |
| Neck Pain | 2 | 1 |
| Viral Infection | 2 | 1 |
| Digestive System | | |
| Vomiting | 15 | 13 |
| Anorexia | 13 | 8 |
| Diarrhea | 8 | 7 |
| Gastroenteritis | 4 | 2 |
| Constipation | 3 | 1 |
| Hemic and Lymphatic System | | |
| Ecchymosis | 4 | 1 |
| Metabolic and Nutritional | | |
| Dehydration | 2 | 1 |
| Nervous System | | |
| Somnolence | 23 | 11 |
| Hostility | 12 | 6 |
| Nervousness | 10 | 2 |
| Personality Disorder | 8 | 7 |
| Dizziness | 7 | 2 |
| Emotional Lability | 6 | 4 |
| Agitation | 6 | 1 |
| Depression | 3 | 1 |
| Vertigo | 3 | 1 |
| Reflexes Increased | 2 | 1 |
| Confusion | 2 | 0 |
| Respiratory System | | |
| Rhinitis | 13 | 8 |
| Cough Increased | 11 | 7 |
| Pharyngitis | 10 | 8 |
| Asthma | 2 | 1 |
| Skin and Appendages | | |
| Pruritus | 2 | 0 |
| Skin Discoloration | 2 | 0 |
| Vesiculobullous Rash | 2 | 0 |
| Special Senses | | |
| Conjunctivitis | 3 | 2 |
| Amblyopia | 2 | 0 |
| Ear Pain | 2 | 0 |
| Urogenital System | | |
| Albuminuria | 4 | 0 |
| Urine Abnormality | 2 | 1 |
Other events occurring in at least 2% of pediatric levetiracetam-treated patients but as or more frequent in the placebo group were the following: abdominal pain, allergic reaction, ataxia, convulsion, epistaxis, fever, headache, hyperkinesia, infection, insomnia, nausea, otitis media, rash, sinusitis, status epilepticus (not otherwise specified), thinking abnormal, tremor, and urinary incontinence.
In well-controlled adult clinical studies, 15% of patients receiving levetiracetam and 11.6% receiving placebo either discontinued or had a dose reduction as a result of an adverse event. Table 12 lists the most common (>1%) adverse events that resulted in discontinuation or dose reduction.
Table 12: Adverse Events That Most Commonly Resulted In Discontinuation Or Dose Reduction In Placebo-Controlled Studies In Adult Patients Experiencing Partial Onset Seizures| | Number (%) |
| | Levetiracetam (N=769) | Placebo (N=439) |
| Asthenia | 10 (1.3%) | 3 (0.7%) |
| Convulsion | 23 (3%) | 15 (3.4%) |
| Dizziness | 11 (1.4%) | 0 |
| Rash | 0 | 5 (1.1%) |
| Somnolence | 34 (4.4%) | 7 (1.6%) |
In the well-controlled pediatric clinical study, 16.8% of patients receiving levetiracetam and 20.6% receiving placebo either discontinued or had a dose reduction as a result of an adverse event. The adverse events most commonly associated (≥3% in patients receiving levetiracetam) with discontinuation or dose reduction in the well-controlled study are presented in Table 13.
Table 13: Adverse Events Most Commonly Associated With Discontinuation Or Dose Reduction In The Placebo-Controlled Study In Pediatric Patients Ages 4 To 16 Years Experiencing Partial Onset Seizures| | Number (%) |
| | Levetiracetam (N=101) | Placebo (N=97) |
| Asthenia | 3 (3%) | 0 |
| Hostility | 7 (6.9%) | 2 (2.1%) |
| Somnolence | 3 (3%) | 3 (3.1%) |