- What is zonisamide-oral, and how does it work (mechanism of action)?
- What is zonisamide-oral used for?
- What are the side effects of zonisamide-oral?
- What is the dosage for zonisamide-oral?
- Which drugs or supplements interact with zonisamide-oral?
- Is zonisamide-oral safe to take if you are pregnant or breastfeeding?
- What else should I know about zonisamide-oral?
What is zonisamide-oral, and how does it work (mechanism of action)?
- Scientists do not known how exactly zonisamide works in the body. Zonisamide is presumed to work on the sodium and calcium channels in the brain cells where it controls electric-currents that are responsible for seizure activity.
- The FDA approved zonisamide in March 2000.
- The brand name for zonisamide is Zonergran.
- Zonisamide is available in generic form. You need a prescription to obtain zonisamide.
What are the side effects of zonisamide-oral?
Common side effects of zonisamide are:
- Dizziness
- Agitation
- Fatigue
- Confusion
- Loss of concentration
- Loss of appetite
- Nausea
- Diarrhea
- Stomach ache
- Headache
- Speech disturbance
- Weight loss
Serious side effects of zonisamide include:
- Psychiatric disorders such as schizophrenia
- Seizures
- Serious skin disorders such as Stevens-Johnson's syndrome or toxic epidermal necrolysis.

QUESTION
If you have had a seizure, it means you have epilepsy. See AnswerWhat is the dosage for zonisamide-oral?
The recommended starting dose of zonisamide is 100 mg/day. Doses may be increased 100 mg/day every 2 weeks. The usual dosage varies from 100 to 600 mg/day, administered in 1 to 2 divided doses.
Safe and effective use of zonisamide is not established for children under the age of 16.
Which drugs or supplements interact with zonisamide-oral?
Zonisamide increases the risk of lactic acid build up when combined with metformin (Glucophage). If you experience sudden weakness, heavy breathing, and increased drowsiness, contact your healthcare professional immediately.
Orlistat (Xenical) should be used with caution with zonisamide because it lowers the beneficial effects of zonisamide and increases the chances of seizures. If you experience dizziness, drowsiness, difficulty walking, nausea, vomiting, and abnormal eye movements, contact your healthcare professional immediately.
Is zonisamide-oral safe to take if you are pregnant or breastfeeding?
- There are no adequate studies done on zonisamide to determine its safe and effective use in pregnant mothers.
- It is not known whether zonisamide is excreted in breast milk. It should be used with caution in females who are nursing.
Summary
Zonisamide (Zonegran) is a prescription drug prescribed as supplemental therapy in treating partial seizures. Side effects, drug interactions, dosing and storage information, and pregnancy safety should be reviewed prior to taking this medication.
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Seizures occur when there is an abnormal burst of electrical activity in the brain and are divided into two categories: generalized and partial. Learn about the symptoms of different types of seizures, and check out the center below for more medical references on seizures, including multimedia (slideshows, images, and quizzes), related diseases, treatment, diagnosis, medications, and prevention or wellness.
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Febrile Seizures
Febrile seizures, or convulsions caused by fever, can be frightening in small children or infants. However, in general, febrile seizures are harmless. Febrile seizure is not epilepsy. It is estimated that one in every 25 children will have at least one febrile seizure. It is important to know what to do to help your child if he/she has a febrile seizure. Some of the features of a febrile seizure include losing consciousness, shaking, moving limbs on both sides of the body, and lasts 1-2 minutes. Less commonly, a febrile seizure may only affect one side of the body.
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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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