Epilepsy zonisamide

MA-St nortriptyline (treatment of depression), fluoxetine (antidepressant), betahistidine (antivertigo drug), metformin (antidiabetic drug), metronidazole (antibiotic), captropril (treatment of hypertension), amantadine (antiviral, anti-parkinson), amlopidine (anti-hypertensive), gabapentin (treatment of epilepsy), zonisamide (anti convulsant), mesalamine (anti-inflamatory) 124,125... 

Discontinuation of therapy Abrupt withdrawal of zonisamide in patients with epilepsy may precipitate increased seizure frequency or status epilepticus. Gradually reduce dose. 

Specific myoclonic syndromes are usually treated with valproate an intravenous formulation can be used acutely if needed. It is nonsedating and can be dramatically effective. Other patients respond to clonazepam, nitrazepam, or other benzodiazepines, although high doses may be necessary, with accompanying drowsiness. Zonisamide and levetiracetam may be useful. Another specific myoclonic syndrome, juvenile myoclonic epilepsy, can be aggravated by phenytoin or carbamazepine valproate is the drug of choice followed by lamotrigine and topiramate. 

Marson AG et al Levetiracetam, oxcarbazepine, remacemide and zonisamide for drug resistant localization-related epilepsy A systematic review. Epilepsy Res 2001 46 259. 

The effects of concomitant carbamazepine, phenytoin, sodium valproate, and zonisamide on the steady-state serum concentrations of clonazepam have been investigated in 51 epileptic in-patients under 20 years of age (14). Serum concentrations of clonazepam correlated positively with the dose of clonazepam and negatively with the doses of carbamazepine and valproic acid, but not with phenytoin or zonisamide. These results confirm that as the oral doses of carbamazepine and sodium valproate increase, the serum concentration of clonazepam falls, but there is no interaction with either phenytoin or zonisamide. In the case of carbamazepine the mechanism of action is thought to be enzyme induction, increasing the metabolism of clonazepam. It is not known what the mechanism is with sodium valproate. In patients with epilepsy, the co-administration of either sodium valproate or carbamazepine will reduce the serum concentration of clonazepam and increase the risk of a seizure. When... 

After an episode of zonisamide-induced psychosis, a 28-year-old man with epilepsy consistently mistook people who were unknown to him, such as hospital staff, for people whom he had met long ago. However, he did not misidentify their names or other attributes, such as their occupations. 

Complex visual hallucinations occurred in three patients taking zonisamide for different syndromes and types of seizures (Landau-Kleffner syndrome in a 7-year-old girl, myoclonic and generalized tonic seizures in a 21-year-old woman, and partial epilepsy in a 13-year-old girl) (692). None of the patients had visual hallucinations before zonisamide was started, and the symptoms resolved after withdrawal. 

Hirose M, Yokoyama H, Haginoya K, Iinuma K. [A five-year-old girl with epilepsy showing forced normalization due to zonisamide] No To Hattatsu 2003 35 259-63. 

Leppik IE. Three new drugs for epilepsy levefiracefam, oxcarbazepine, and zonisamide. J Child Neurol. 2002 f7 SuppI f S53-7. 

Zonisamide is itself a second-line augmenting agent to numerous other agents in treating conditions other than epilepsy, such as bipolar disorder, chronic neuropathic pain, and migraine... 

Lack of convincing efficacy for treatment of conditions other than epilepsy suggests risk/benefit ratio is in favor of discontinuing zonisamide during pregnancy for these indications... 

Due to reported weight loss in some patients in trials with epilepsy, some patients with psychotropic-induced weight gain are treated with zonisamide... 

Chadwick DW, Marson AG. Zonisamide add-on for drug-resistant partial epilepsy. Cochrane Database Syst Rev. 2002 (2) CD00f4f6. 

GlauserTA, Pellock JM. Zonisamide in pediatric epilepsy review of the Japanese experience. J Child Neurol. 2002 f 7 87-96. 

Three patients with severe myoclonic epilepsy in infancy developed choreoathetosis after an increase in phenytoin dosage it resolved when the phenytoin dosage was reduced (17). In one, an ictal SPECT showed reduced perfusion in the basal ganglia contralateral to the unilateral choreoathetosis. Polypharmacy, including carbama-zepine and zonisamide, may have facilitated the onset of choreoathetosis. 

Peters DH, Sorkin EM. Zonisamide. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in epilepsy. Drugs 1993 45(5) 760-87. 

Marson AG, Hutton JL, Leach JP, Castillo S, Schmidt D, White S, Chaisewikul R, Privitera M, Chadwick DW. Levetiracetam, oxcarbazepine, remacemide and zonisamide for drug resistant localization-related epilepsy a systematic review. Epilepsy Res 2001 46(3) 259-70. 

Kubota M, Nishi-Nagase M, Sakakihara Y, Noma S, Nakamoto M, Kawaguchi H, Yanagisawa M. Zonisamide-induced urinary lithiasis in patients with intractable epilepsy. Brain Dev 2000 22(4) 230-3. 

Certain anticonvulsants developed initially for the treatment of epilepsy, such as topiramate and zonisamide, have been found to have a beneficial effect in mood disorders, particularly bipolar disorder. In addition, patients treated with these compounds lose weight. They were therefore seen as potential therapeutic agents for use in obese patients with BED. 

The traditional treatment of tonic-clonic seizures is phenytoin or phenobarbital however, the use of carbamazepine and valproic acid is increasing because these AEDs have a lower incidence of side effects and equal efficacy. Valproic acid generally is considered the drug of first choice for atonic seizures and for juvenile myoclonic epilepsy. Lamotrigine and perhaps topiramate and zonisamide may be alternative agents for these seizure types. 

THERAPEUTIC USE Clinical trials of patients with refractory partial seizures demonstrated that addition of zonisamide to other drugs was superior to placebo. Its efficacy as monotherapy for newly diagnosed or refractory epilepsy remains unproven. 

Abo J, Miura H, Takanashi S, Shirai H, Sunaoshi W, Hosoda N, Abo K, Takei K. Drug interaction between zonisamide and carbamazepine a pharmacokinetic study in children with cryptogenic localization-related epilepsies. Epilepsia (1995) 36 (Suppl 3), S162. 

Rosenfeld WE, Bergen D, Garnett W, Shah J, Floren LC, Gross J, Tupper R, Shellenberger K. Steady-state drug interaction study of zonisamide and carbamazepine in patients with epilepsy. Neurolo (2001) 56 (Suppl 3), A336. 

Ragueneau-Majlessi I, Levy RH, Bergen D, Garnett W, Rosenfeld W, Mather G, Shah J, Grundy JS. Carbamazepine pharmacokinetics are not affected by zonisamide in vitro mechanistic study and in vivo clinical study in epileptic patients. Epilepsy Res ( 004) 62, 1-11. 

Schm idt D, Jacob R, Loiseau P, Deisenhammer E, Klinger D, Despland A, Egli M, Bauer G, Stenzel E, Blankenhom V. Zonisamide for add-on treatment of refractory partial epilep a European double-blind trial. Epilepsy Res 99y) 15, 61-13>. 

Levy RH, Ragueneau-Majlessi I, Brodie MJ, Smith DF, Shah J, W-J. Lack of clinically significant plmimacdcinetic interactions between zonisamide and lamotrigine at steacty state in patients with epilepsy. Ther Drug Monit (2005) 27,193-8. 

Levy RH, R ueneau-Majlessi I, Garnett hmerler M, Rosenfeld W, Shah J, Pan W-J. Lack of a clinically signiHcant effect of zonisamide on phenytoin sted[Pg.581]

An 20-year-old HIV-positive man with epilepsy, who had his seizures controlled with carbamazepine 350 mg twice daily and zonisamide 140 mg twice daily, was admitted to hospital for review of his antiretrovirals. He started taking ritonavir 200 mg three times daily, but after the first dose of ritonavir his serum carbamazepine levels rose from 9.5 to... 

A patient with bitemporal epilepsy took lacosamide 12 g, gabapentin 56 g, topira-mate 2 g, and zonisamide 2.8 g [104 ]. He became comatose and had repeated generalized tonic-clonic seizures, aspiration, and subsequent pneumonia, hypotension, and first-degree atrioventricular block. He recovered completely after several days of supportive treatment. 

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