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zonisamide

Zonegran · ATC code N03AX15

Also known as: Zonisamid · Brand names: Zonegran, Zonisamid Aristo, Epizonya, Excegran, Zalipin

Key facts
Active substance
zonisamide
Drug class
Anticonvulsant agent
ATC code
N03AX15
Authorisation
centrally authorised across the EU (EMA)
Dosage forms
Zonegran 25 mg hard capsules · Zonegran 50 mg hard capsules · Zonegran 100 mg hard capsules
Marketing authorisation holder
Amdipharm Limited
Information as of
2026-10-27

Key facts

Zonisamide is an antiepileptic benzisoxazole derivative containing a sulphonamide group (Zonegran hard capsules). It is used for partial seizures with or without secondary generalisation.

What it is used for

  • Monotherapy of partial seizures in adults with newly diagnosed epilepsy
  • Adjunctive therapy of partial seizures in adults, adolescents and children aged 6 years and above

Dosing

  • Monotherapy, adults: weeks 1 + 2 100 mg/day, weeks 3 + 4 200 mg/day, then 300 mg/day once daily; up to a maximum of 500 mg if needed
  • Adjunctive therapy, adults with CYP3A4 inducers: start 50 mg/day, increase weekly; maintenance 300 to 500 mg per day
  • Without CYP3A4 inducers or with renal/hepatic impairment: slower increases at two-weekly intervals
  • Children 6 years and above: start 1 mg/kg/day, maintenance 6 to 8 mg/kg/day (over 55 kg 300 - 500 mg/day)
  • Withdraw gradually to avoid withdrawal seizures

Contraindications

  • Hypersensitivity to the active substance, any excipient or sulphonamides
  • Allergy to peanut or soya (contains hydrogenated soyabean oil)

Important warnings

  • Serious rashes including Stevens-Johnson syndrome; consider stopping for unexplained rash
  • Sulphonamide reactions including aplastic anaemia, very rarely fatal
  • Kidney stones and hyperchloraemic metabolic acidosis
  • Decreased sweating and heat stroke, mainly in children; weight loss

Side effects

  • Adjunctive therapy: most common somnolence, dizziness and anorexia
  • Monotherapy: most common decreased bicarbonate, decreased appetite and decreased weight
  • Rare serious: Stevens-Johnson syndrome, haematological disturbances

Interactions

  • CYP3A4 inducers affect the dose needed (faster titration possible)
  • Carbonic anhydrase inhibitors (e.g. topiramate, acetazolamide): caution in adults, not to be combined in children
  • Medicines with anticholinergic activity increase the risk of heat-related disorders

Pregnancy and breastfeeding

  • Pregnancy: limited data; registry data suggest more babies born with low birth weight, pre-term or small for gestational age
  • Breast-feeding: excreted in human milk; do not resume until one month after stopping therapy

Summary of the official product information, written with AI (Claude, Anthropic) on 2026-10-28. Every number was checked automatically against the original text. Not reviewed by a physician – the full official text is authoritative.

Full official text →

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For patients

Package leaflet, verbatim

Package leaflet for patients →

Authorisation and brand names by country

Medicines with exactly this active-substance composition, as listed in the national registers – alphabetical and without ranking. Whether a product is currently available is not shown here.

EU – centrally authorised (all member states)

Source: European Medicines Agency (EMA), product information

Austria

  • Zonisamid AristoAristo Pharma Gmbh (Art 57) · 1 register entry

Source: EMA – Article 57 product data (EU/EEA), as of 2026-10-28

Germany

  • Zonisamid1 A Pharma Gmbh, Neuraxpharm Arzneimittel Gmbh, Ratiopharm Gmbh, Glenmark Arzneimittel Gmbh, Desitin Arzneimittel Gmbh, Accord Healthcare B.V., Aristo Pharma Gmbh (Art 57), Puren Pharma Gmbh & Co. Kg, Betapharm Arzneimittel Gmbh · 9 register entries

Source: EMA – Article 57 product data (EU/EEA), as of 2026-10-28

Turkey

  • EpizonyaLİBA LABORATUARLARI A.Ş. · 3 register entries
  • ExcegranSANOFİ SAĞLIK ÜRÜNLERİ LTD. ŞTİ. · 1 register entry
  • ZalipinGENVEON İLAÇ SAN. VE TİC. A.Ş. · 1 register entry

Source: TİTCK – Ruhsatlı Beşeri Tıbbi Ürünler Listesi, as of 2026-10-16

Brand names in 22 more European countries
Bulgaria
Зокап
Croatia
Zocap
Czechia
Ersittin, Zonisamid Sandoz, Zonisamide Neuraxpharm
Denmark
Zonisamid Desitin, Zonisamid Glenmark, Zonisamide, Zopnisamide Teva
Estonia
Zonisamide Sandoz
Finland
Zonisamide Desitin
France
Zonisamide Arrow, Zonisamide Neuraxpharm, Zonisamide Sandoz, Zonisamide Teva
Iceland
Zonegran, Zonisamide Viatris
Ireland
Zonisamide Desitin, Zonisamide Rowex
Italy
Zonisamide Doc Generici, Zonisamide Sandoz
Liechtenstein
Zonegran, Zonisamide Viatris
Lithuania
Zonisamide Sandoz
Malta
Zonisamide Doc Generici
Netherlands
Zonisamide Indoco, Zonisamide Sandoz
Norway
Zonegran, Zonisamid Desitin, Zonisamide Viatris
Poland
Zonisamidum Neuraxpharm
Portugal
Zonisamida Aristo, Zonisamida Generis, Zonisamida Ipca, Zonisamida Pentafarma, Zonisamida Ratiopharm, Zonisamida Tolife
Romania
Zocap, Zonisamidă Desitin
Slovakia
Zonisamide Neuraxpharm
Slovenia
Zocap, Zonisamid Sandoz
Spain
Nyzol, Zonesme, Zonisamida Aristo, Zonisamida Aurovitas, Zonisamida Cinfamed, Zonisamida Kern Pharma, Zonisamida Normon, Zonisamida Sandoz, Zonisamida Stada, Zonisamida Tarbis, Zonisamida Teva, Zonisamida Viso Farmacéutica
Sweden
Zonisamide

EMA – Article 57 product data (EU/EEA), 2026-10-28

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Sources

  1. European Medicines Agency. Zonegran – EPAR, Product Information (OF THE TEXT Detailed information on this medicinal product i). 2026-10-27. https://www.ema.europa.eu/en/documents/product-information/zonegran-epar-product-information_en.pdf
  2. EMA – Article 57 product data (EU/EEA), 2026-10-28. https://www.ema.europa.eu/en/human-regulatory-overview/post-authorisation/data-medicines-iso-idmp-standards-post-authorisation/public-data-article-57-database
  3. EMA – Article 57 product data (EU/EEA), 2026-10-28. https://www.ema.europa.eu/en/human-regulatory-overview/post-authorisation/data-medicines-iso-idmp-standards-post-authorisation/public-data-article-57-database
  4. TİTCK – Ruhsatlı Beşeri Tıbbi Ürünler Listesi, 2026-10-16. https://www.titck.gov.tr/dinamikmodul/85
  5. Wikidata (CC0): ATC N03AX.

Editorial: Medelix editorial team · last updated 2026-10-27 · How these pages are made · Report an error

Source: European Medicines Agency (EMA), product information. Not advertising, not a treatment recommendation. For questions about your own treatment, ask your doctor or pharmacist.