Memory impairment topiramate

Observational studies In a prospective, long-term observational study of topiramate as initial monotherapy in 229 Chinese patients with newly diagnosed epilepsy the retention rate was 76% at 1 year and 47% at 6 years [278 ]. Causes that led to treatment failure were lack of efficacy (7.4%), adverse reactions (11%), and loss to follow-up (16%). Adverse reactions occurred in 129 patients (56%). The most common included memory impairment (13%), weight loss (8.7%), nausea (7.3%), speech difficulty (5.7%), and somnolence (4.8%). Seven patients (3.1%) developed renal calculi. Most of the adverse reactions occurred in the first 6 months of treatment, especially during the titration period. 

Observational studies Topiramate has been retrospectively evaluated in 227 patients with symptomatic epilepsy, of whom 12 withdrew because of adverse effects [292 ]. The incidence of adverse effects was 36% and the most common were weight loss, memory impairment, paresthesia, headache, and dizziness, most were mild to moderate in intensity and transient. 

In a single-center, 8-week titration and 4-week maintenance period, double-blind, randomized study of topiramate or amitriptyline, alone or in combination, in 73 patients with migraine with or without aura all the treatments resulted in significant improvements in all efficacy measures [296 ]. Discontinuation rates due to adverse events were 8.3%, 14%, and 4.3% with topiramate, amitriptyline, and the combination respectively. The most common adverse effects in the topiramate group were paresthesia (35% at 8 weeks and 40% at 12 weeks), weight loss (25% and 35% respectively), and memory impairment (10% and 15%, respectively). 

Topiramate cognitive slowing, impairment of verbal memory, word-finding difficulties, reduced psychomotor speed (Sachdeo and Karia, 2002). 

I Disadvantages. With rapid dosage escalation, topiramate may compromise cognitive fnnctioning, including impaired word finding and short-term memory. Therefore, low initial doses should be used, and the dose must be titrated slowly. Renal stones and weight loss also have been associated with topiramate use. The dose should be decreased in patients with renal failure. There is no parenteral formulation. 

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