Antiepileptics topiramate

PHENYTOIN 1. LAMOTRIGINE 2. TIAGABINE 3. TOPIRAMATE 4. VALPROATE 5. ZONISAMIDE 1 levels of these antiepileptics. Topiramate sometimes t phenytoin levels Induction of metabolism. Uncertain why phenytoin alters topiramate levels Watch for poor response to these antiepileptics... 

Preliminary results of a study show that rufinamide 800 mg twice daily for 14 days decreased the AUC of ethinylestradiol 35 micrograms hy 22% and of norethisterone 1 mg by 14% in healthy women taking a combined oral contraceptive. Inhibition of ovulation was not assessed. These reductions in plasma levels of the contraceptive hormones are similar to those seen with topiramate (see Hormonal contraceptives + Antiepileptics Topiramate , below), and their clinical relevance is unknown. However, given these findings, low-dose contraceptives (ethinylestradiol 20 micrograms) may be considered unsuitable for use with rufinamide. Further study is needed. 

Some sugar-derived dmgs obtained by chemical means have also achieved some importance, for example, ranitidine (Zantac ), an inhibitor of gastric acid secretion—one of the top 30 drugs based on sales —isosorbide dinitrate, a coronary vasodilatator, or topiramate, a fructose-derived anticolvulsant drug with high antiepileptic efficacy. ... 

Curry, W.J. and Kulling, D.L. (1998) Newer antiepileptic drugs ga-bapentin, lamotrigine, felbamate, topiramate and fosphenytoin. Am Fam Physician 57 513-520. 

Topiramate, another antiepileptic drug, may also be helpful in a dose of 400 mg daily, built up gradually. Small quantities of alcohol may suppress essential tremor but only for a short time. Alprazolam (in doses up to 3 mg daily) or gabapentin (100-2400 mg/d) is helpful in some patients. Others are helped by intramuscular injections of botulinum toxin. Thalamic stimulation by an implanted electrode and stimulator is often worthwhile in advanced cases refractory to pharmacotherapy. Diazepam, chlordiazepoxide, mephenesin, and antiparkinsonism agents have been advocated in the past but are generally worthless. Anecdotal reports of benefit from mirtazapine were not confirmed in a double-blind study, which found no effect on the tremor in most patients. 

Changes in body weight associated with anticonvulsants have been reviewed (116), including the effects of the antiepileptic drugs that have been most commonly associated with this adverse effect (valproic acid, carbamazepine, vigabatrin, and gabapentin) (117). Unlike most anticonvulsants, topiramate, felbamate, and zonisamide can cause weight loss. 

Angehagen M, Ben-Menachem E, Ronnback L, Hans-son E. Novel mechanisms of action of three antiepileptic drugs, vigabatrin, tiagabine, and topiramate. Neurochem Res. 2003 28 333-340. 

Mode of action. Topiramate has multiple actions which contribute to its antiepileptic potential. It appears that its most important action is its inhibitory effect on sodium conductance in neuronal membranes, an action... 

Side effects. Many of the side effects reported to occur with topiramate have been found in patients receiving other antiepileptic drugs concurrently. Such side effects as ataxia, confusion, dizziness, fatigue, somnolence, memory disturbance, depression and agitation appear to be less frequent in those patients receiving topiramate as a monotherapy. Weight loss has been reported in many patients this effect may be due to drug induced anorexia. Topiramate has proven efficacious in the treatment of severe epilepsy. 

Topiramate analogue 168 was enlisted into a comprehensive structural-activity relationship study [37], along with about a hundred varied synthetic analogues, which allowed identification of a new promising antiepileptic lead. From this study, carba-analogue 168 resulted three times more active than its corresponding carbohydrate-based drug. 

Outlook Among the newer antiepileptics, gabapentin, oxycarbazepine, lamotrigine, and topiramate are now endorsed as primary monotherapeutics for both partial and generalized seizures. Their pharmacokinetic characteristics are generally more desirable than those of the older drugs. 

Chu (4) demonstrated that the sustained use of the antiepileptic drug, Topiramate , (IV), was effective in treating age-related macular degeneration by inducing growth of new optic nerve. 

Topiramate Multiple CNS effects antiepileptic Psychomotor Poor patient... 

Topiramate is an antiepileptic medication also used in an off-label capacity to treat migraine headaches and bipolar disorders. 

The use of antiepileptic drugs (gabapentin, lamotrigine, and topiramate) as mood stabilizers has been... 

Perucca E, Bialer M. The clinical pharmacokinetics of the newer antiepileptic drugs. Focus on topiramate, zonisamide and tiagabine. Clin Pharmacokinet 1996 31(1) 29 6. 

In an open study of the effects of topiramate 100-1600 mg/day in 292 adults (mean age 33 years) with partial and/or generalized seizures previously resistant to antiepileptic drug therapy over 50% of the patients achieved at least a 50% reduction in seizures (1). The most commonly reported adverse events were related to the central nervous system, including headache, difficulty in concentrating, somnolence, anorexia, fatigue, dizziness, nervousness, nausea, confusion, and paresthesia 32% discontinued because of adverse events. 

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