The most commonly observed adverse events related to treatment with zonisamide capsules (an incidence at least 4% greater than placebo) in controlled clinical trials and shown in descending order of frequency were somnolence, anorexia, dizziness, ataxia, agitation/irritability, and difficulty with memory and/or concentration.
In controlled clinical trials, 12% of patients receiving zonisamide capsules as adjunctive therapy discontinued due to an adverse event compared to 6% receiving placebo. Approximately 21% of the 1,336 patients with epilepsy who received zonisamide capsules in clinical studies discontinued treatment because of an adverse event. The adverse events most commonly associated with discontinuation were somnolence, fatigue and/or ataxia (6%), anorexia (3%), difficulty concentrating (2%), difficulty with memory, mental slowing, nausea/vomiting (2%), and weight loss (1%). Many of these adverse events were dose-related (see
Other Adverse Events Observed During Clinical Trials:
Zonisamide capsules has been administered to 1,598 individuals during all clinical trials, only some of which were placebo-controlled. During these trials, all events were recorded by investigators using their own terms. To provide a useful estimate of the proportion of individuals having adverse events, similar events have been grouped into a smaller number of standardized categories using a modified COSTART dictionary. The frequencies represent the proportion of the 1,598 individuals exposed to zonisamide capsules who experienced an event on at least one occasion. All events are included except those already listed in the previous table or discussed in WARNINGS
, trivial events, those too general to be informative, and those not reasonably associated with zonisamide capsules.
Events are further classified within each category and listed in order of decreasing frequency as follows: frequent
occurring in at least 1:100 patient; infrequent
occurring in 1:100 to 1:1000 patients; rare
occurring in fewer than 1:1000 patients.
Body as a Whole: Frequent:
Accidental injury, asthenia. Infrequent:
Chest pain, flank pain, malaise, allergic reaction, face edema, neck rigidity. Rare:
Palpitation, tachycardia, vascular insufficiency, hypotension, hypertension, thrombophlebitis, syncope, bradycardia. Rare:
Atrial fibrillation, heart failure, pulmonary embolus, ventricular extrasystoles.
Flatulence, gingivitis, gum hyperplasia, gastritis, gastroenteritis, stomatitis, cholelithiasis, glossitis, melena, rectal hemorrhage, ulcerative stomatitis, gastro-duodenal ulcer, dysphagia, gum hemorrhage. Rare:
Cholangitis, hematemesis, cholecystitis, cholestatic jaundice, colitis, duodenitis, esophagitis, fecal incontinence, mouth ulceration.
Hematologic and Lymphatic: Infrequent:
Leukopenia, anemia, immunodeficiency, lymphadenopathy. Rare:
Thrombocytopenia, microcytic anemia, petechia.
Metabolic and Nutritional: Infrequent:
Peripheral edema, weight gain, edema, thirst, dehydration. Rare:
Hypoglycemia, hyponatremia, lactic dehydrogenase increased, SGOT increased, SGPT increased.
Leg cramps, myalgia, myasthenia, arthralgia, arthritis.
Nervous System: Frequent:
Tremor, convulsion, abnormal gait, hyperesthesia, incoordination. Infrequent:
Hypertonia, twitching, abnormal dreams, vertigo, libido decreased, neuropathy, hyperkinesia, movement disorder, dysarthria, cerebrovascular accident, hypotonia, peripheral neuritis, reflexes increased. Rare: Dyskinesia, dystonia, encephalopathy, facial paralysis, hypokinesia, hyperesthesia, myoclonus, oculogyric crisis.
Behavioral Abnormalities - Non-Psychosis-Related: Infrequent:
Pharyngitis, cough increased. Infrequent:
Skin and Appendages: Frequent:
Maculopapular rash, acne, alopecia, dry skin, sweating, eczema, urticaria, hirsutism, pustular rash, vesiculobullous rash.
Special Senses: Frequent:
Amblyopia, tinnitus. Infrequent:
Conjunctivitis, parosmia, deafness, visual field defect, glaucoma. Rare:
Urinary frequency, dysuria, urinary incontinence, hematuria, impotence, urinary retention, urinary urgency, amenorrhea, polyuria, nocturia. Rare:
Albuminuria, enuresis, bladder pain, bladder calculus, gynecomastia, mastitis, menorrhagia.