Find information on thousands of medical conditions and prescription drugs.

Zonisamide

Zonisamide (brand name Zonegran®) is a sulfonamide anticonvulsant approved for use as an adjunctive therapy in adults with partial-onset seizures. It was discovered by researchers at Dainippon Sumitomo Pharma (大日本住友製薬: Dainippon Sumitomo Seiyaku (formerly Dainippon Pharmaceutical (大日本製薬: Dainippon Seiyaku)), who launched it in 1989 as Excegran® in Japan. It was marketed by Élan in the United States starting in 2000 as Zonegran®, before Élan transferred their interests in zonisamide to Eisai (エーザイ) in 2004. more...

Home
Diseases
Medicines
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Zafirlukast
Zagam
Zalcitabine
Zaleplon
Zanaflex
Zanamivir
Zantac
Zarontin
Zelnorm
Zerit
Zestoretic
Zestril
Zetia
Zevalin
Ziagen
Zidovudine
Zileuton
Ziprasidone
Zithromax
Zocor
Zofran
Zoladex
Zoledronic acid
Zolmitriptan
Zoloft
Zolpidem
Zometa
Zomig
Zonegran
Zonisamide
Zopiclone
Zosyn
Zovia
Zovirax
Zyban
Zymar
Zyprexa
Zyrtec
Zyvox

Eisai also markets Zonegran® in Asia (China, Taiwan, and fourteen others) and Europe (starting in Germany and the United Kingdom).

Uses

Approved

Zonisamide is approved in the United States, United Kingdom, and Japan for adjunctive treatment of partial seizures in adults.

Unapproved/Off-Label/Investigational

An open trial on zonisamide in seven Parkinson's disease patients had positive results, according to this 2001 report. Since then, it has been reported to treat the resting tremor that other therapies may leave behind. By early November of 2005, Dainippon Sumitomo had filed a NDA for the use of zonisamide in Parkinson's disease; it is to be marketed as Tremode®.

Metabolism

Zonisamide is metabolized mostly by the CYP3A4 isoenzyme, but also CYP3A7 and CYP3A5, to 2-(sulphamoylacetyl)-phenol via reductive cleavage of the 1,2-benzisoxazole ring.

Mechanism of Action

The exact mechanism of action is not known for zonisamide. According to Leppik, while zonisamide may be a carbonic anhydrase inhibitor like acetazolamide, this is not one of the primary mechanisms of action, which might be blocking repetitive firing of voltage-gated sodium channels and reduction of T-type calcium channel currents, or by binding allosterically to GABA receptor like the benzodiazepines and muscimol, or increasing the levels of the glutamate transport protein in the brain while decreasing the amount of GABA transport protein, in other words, inhibiting the uptake of the inhibitory neurotransmitter GABA while enhancing the uptake of the excitatory neurotransmitter glutamate.

Read more at Wikipedia.org


[List your site here Free!]


Zonisamide May Help Patients with Medication-Resistant Epilepsy
From American Family Physician, 10/15/99 by Verna L. Rose

(American Academy of Neurology) Zonisamide (Zonegran), a drug under investigation in the United States, appears to be effective in the treatment of patients with epilepsy who have not responded to an antiepileptic drug, according to a U.S. study of eight patients with medication-resistant epilepsy who participated in a series of long-term trials of zonisamide. All of the patients had partial seizures that were inadequately controlled by a number of antiepileptic drugs before starting the trial of zonisamide. The patients in the study received zonisamide from 9.7 to 12.2 years (mean treatment duration: 11.0 years). The dosage ranged from 100 to 1,000 mg daily (mean: 500 to 700 mg daily). The most common side effects were ataxia, viral illness, dizziness, and forgetfulness or slowness of thought. Adverse events occurred most often during the initiation of therapy and became less frequent or less severe over time. The investigators believe that most patients with medication-resistant epilepsy will benefit from a total dosage of about 400 mg daily.-mark l. scheuer, m.d., et al., Comprehensive Epilepsy Center, University of Pittsburgh, Pittsburgh, Pa.

COPYRIGHT 1999 American Academy of Family Physicians
COPYRIGHT 2000 Gale Group

Return to Zonisamide
Home Contact Resources Exchange Links ebay