Donepezil treatment of topiramate-related cognitive dysfunction

Effects of topiramate on language functions in newly diagnosed pediatric epileptic patients

BACKGROUND

The aim of this study was to characterize the effects of topiramate on language functions in newly diagnosed pediatric epileptic patients.

METHODS

Thirty-eight newly diagnosed epileptic patients were assessed using standard language tests. Data were collected before and after beginning topiramate during which time a monotherapy treatment regimen was maintained. Language tests included the Test of Language Problem Solving Abilities, a Korean version of the Peabody Picture Vocabulary Test. We used language tests in the Korean version because all the patients were spoken Korean exclusively in their families.

RESULTS

All the language parameters of Test of Language Problem Solving Abilities worsened after initiation of topiramate (determine cause, 13.2 ± 4.8 to 11.2 ± 4.3; problem solving, 14.8 ± 6.0 to 12.8 ± 5.0; predicting, 9.8 ± 3.6 to 8.8 ± 4.6). Patients given topiramate exhibited a shortened mean length of utterance in words during response (determine cause, 4.8 ± 0.9 to 4.3 ± 0.7; making inference, 4.5 ± 0.8 to 4.1 ± 1.1; predicting, 5.2 ± 1.0 to 4.7 ± 0.6; P < 0.05), provided ambiguous answers during the testing, exhibited difficulty in selecting appropriate words, took more time to provide answers, and used incorrect grammar. However, there were no statistically significant changes in the receptive language of patients after taking topiramate (95.4 ± 20.4 to 100.8 ± 19.1).

CONCLUSIONS

Our data suggest that topiramate may have negative effects on problem-solving abilities in children. We recommend performing language tests should be considered in children being treated with topiramate.

Safety of topiramate for treating migraines

INTRODUCTION

Migraine is a very common medical disorder characterized by attacks of moderate-severe headache, nausea and disability. Topiramate is an effective, popular prophylactic migraine treatment, which is approved for use in adults and adolescents. Due to its multiple mechanisms of action, topiramate has multiple potential safety issues, including systemic and CNS adverse events, which may complicate therapy.

AREAS COVERED

This review evaluates common adverse events as seen in the pivotal trials of topiramate for migraine as well as those observed in postmarketing studies. These include weight loss, metabolic acidosis, renal calculi, acute angle closure glaucoma, visual distortions and cognitive slowing. Topiramate use during pregnancy is associated with an increased risk of cleft lip. This review highlights both common and unusual safety issues associated with topiramate use, including important drug interactions and a comparison with other migraine prophylactic agents.

EXPERT OPINION

Topiramate is highly effective in migraine prophylaxis but clinicians using the drug need to be aware of the potential for bothersome or serious adverse events. When treating with topiramate, use a slow titration to the goal dose of 100 mg or the lowest dose, which helps prevent migraine.

Cognitive changes in topiramate-treated patients with alcoholism: a 12-week prospective study in patients recently detoxified

AIMS

The aim of this study was to determine the 12-week cognitive changes in topiramate-treated patients recently detoxified from alcohol.

METHODS

Participants were inpatients with DSM-IV alcohol dependence. All of them were discharged within 14 days after the initiation of topiramate treatment. The topiramate dose range was 50-300 mg/day. The Montreal Cognitive Assessment (MoCA) was used on day 0, day 29, day 57, and day 85. Differences of the MoCA total and seven subtest scores among four time-points were compared.

RESULTS

Thirty-eight participants (36 men and two women) had a mean ± SD age of 43.1 ± 8.6 years old. At enrollment, they were abstinent for a mean ± SD of 11.5 ± 5.3 days. Five, one, and three patients dropped out of the study on day 29, day 57, and day 85, respectively. On day 85, the mean ± SD dose of topiramate was 253.1 ± 60.8 mg/day. Alcohol consumption decreased drastically during follow up. At each time-point, 75%-80% of the participants were continuous abstainers. The mean ± SD MoCA total, language subtest, and delayed recall subtest scores increased significantly from day 0 to day 85, from 22.0 ± 4.7 to 24.7 ± 3.4 (P < 0.01), from 1.1 ± 1.0 to 1.3 ± 1.0 (P = 0.03), and from 2.7 ± 1.7 to 4.1 ± 1.0 (P < 0.01), respectively.

CONCLUSION

Topiramate-treated patients recently detoxified from alcohol usually have an improvement of their cognitive function, especially in the language and delayed recall domains. This phenomenon may be caused by the greater influence of cognitive recovery associated with decreased drinking as compared with topiramate-induced cognitive impairment.

Modulation of ion channels in clinical psychopharmacology: adults and younger people

This review focuses on the use of Na(+), Ca(2+) and Cl(-) channel modulators in psychiatric disease. Drugs that modulate ion channels have been used in psychiatry for more than a century, and in this review we critically evaluate clinical research that reports the therapeutic effects of drugs acting on GABA(A), voltage-gated Na(+) and voltage-gated Ca(2+) channels in pediatric and adult patients. As in other fields, the evidence underpinning the use of medicines in younger people is far less robust than for adults. In addition, we discuss some current developments and highlight clinical disorders in which current molecules could be further tested. Notable success stories, such as benzodiazepines (in sleep and anxiety disorders) and antiepileptics (in bipolar disorder), have been the result of serendipitous discoveries or refinements of serendipitous discoveries, as in all other major treatments in psychiatry. Genomic, high-throughput screening and molecular pharmacology discoveries may, however, guide further developments in the future. This could include increased research in promising targets that have been perceived as commercially risky, such as selective α-subunit GABA(A) receptors.

Familial vulnerability to an unusual cognitive adverse effect of topiramate: Discussion of mechanisms

BACKGROUND

Some patients experience cognitive disturbances with topiramate.

CASE HISTORIES

A 19-year-old bipolar woman and her 46-year-old mother with paranoid personality disorder both used topiramate (25-50 mg/day) off-label for weight loss. Both women suffer from learning disorders, and both are excessively sensitive to the sedative adverse effects of psychotropic medications.

RESULTS

Within days of starting topiramate, the women began to exhibit troublesome word- and phrase-repetition and word substitution, both occurring only in their written expression. The symptoms were associated with mild sedation, persisted during two weeks of topiramate treatment, and remitted days after topiramate was withdrawn.

DISCUSSION

The presence of the learning disorders and the sensitivity to the sedative adverse effects of drugs may explain why cognitive adverse effects, known to occur with topiramate, developed at the low dose of 25-50 mg/day. The proclivity of topiramate to affect language functions and a possible familial vulnerability herein may explain why the women explained similar, language-specific symptoms. An investigation of topiramate-induced cognitive impairments in family members with epilepsy may throw light on the subject.

Molecular pharmacodynamics, clinical therapeutics, and pharmacokinetics of topiramate

Topiramate (TPM; TOPAMAX) is a broad-spectrum antiepileptic drug (AED) that is approved in many world markets for preventing or reducing the frequency of epileptic seizures (as monotherapy or adjunctive therapy), and for the prophylaxis of migraine. TPM, a sulfamate derivative of the naturally occurring sugar D-fructose, possesses several pharmacodynamic properties that may contribute to its clinically useful attributes, and to its observed adverse effects. The sulfamate moiety is essential, but not sufficient, for its pharmacodynamic properties. In this review, we discuss the known pharmacodynamic and pharmacokinetic properties of TPM, as well as its various clinically beneficial and adverse effects.

Safety and efficacy of anticonvulsants in elderly patients with psychiatric disorders: oxcarbazepine, topiramate and gabapentin

Few controlled studies are available to guide the clinician in treating potentially assaultive elderly individuals with psychiatric disorders. Safety concerns limit the use of benzodiazepines and antipsychotic medications in the elderly individual, making anticonvulsants an attractive alternative. This paper reviews three specific anticonvulsants for this purpose: gabapentin, oxcarbazepine and topiramate, describing safety and efficacy in elderly patients with severe agitation from psychosis or dementia. Gabapentin, renally excreted, with a half-life of 6.5-10.5 h, may cause ataxia. Oxcarbazapine, hepatically reduced, may cause hyponatremia, and topiramate may cause significant cognitive impairment. Nonetheless, these are important medications to consider in the treatment of agitation.