Topiramate, a concealed cause of severe metabolic acidosis

Abstract

Severe metabolic acidosis is common among critically ill patients, and topiramate is a rare cause that may fail recognition. We report a lady with acute encephalopathy who had severe non-anion gap metabolic acidosis that served as the clue leading to suspicion and diagnosis of topiramate toxicity and was confirmed by elevated blood topiramate levels. Additionally, we provide a review of literature on all reported cases of topiramate toxicity.

Topiramate-Induced Coma in a 39-Year-Old Female Patient: Burst Suppression on EEG

“…Additionally, a strong history suggesting ingestion was provided by the family after finding an empty bottle of recently filled topiramate. The review done by Lovinger et al [ 11 ] suggests that topiramate can cause severe symptomatic NAGMA even when at therapeutic levels. NAGMA experienced during hospitalization (Table 1 ) resolved within two days of presentation and is consistent with topiramate activity against carbonic anhydrase CA-II and CA-IV isoenzymes [ 8 , 9 ].…”