topiramate and Hypokalemia

The use of topiramate, which is prescribed for the management of epilepsy, for migraine headache prophylaxis and as a weight-loss agent, has been associated with the development of metabolic acidosis, hypokalaemia and renal stone disease. We systematically reviewed all the literature.. The systematic review of the literature was realized using the principles underlying the UK Economic and Social Research Council guidance on the conduct of narrative synthesis and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.. Fourty-seven reports published between 1996 and 2013 were retained for the final analysis. Five case-control studies and six longitudinal studies addressed the effect of topiramate on acid-base and potassium balance. A significant tendency towards mild-to-moderate hyperchloraemic metabolic acidosis (with bicarbonate ≤21.0 mmol l(-1) in approximately every third case) and mild hypokalaemia (with potassium ≤3.5 mmol l(-1) in 10% of the cases) was noted on treatment with topiramate, which was similar in children and adults. A single study observed that topiramate causes mild hyperuricaemia in male adults. A tendency towards hypocitraturia, a recognized promoter of renal stone formation, was noted in all patients on topiramate.. Increasing evidence supports the use of topiramate. Topiramate is generally well tolerated, and serious adverse events are rare. Nonetheless, the present systematic review of the literature indicates that its use is linked with the development of acidosis, hypokalaemia, hyperuricaemia and hypocitraturia.

Topics: Acidosis; Female; Fructose; Humans; Hypokalemia; Kidney Calculi; Male; Topiramate

To describe renal tubular acidosis (RTA) and secondary acquired hyperaldosteronism in a cat as an adverse effect of topiramate therapy.. An 8-year-old neutered female cat on chronic oral topiramate therapy at a recommended dose (11.9 mg/kg q 8 h) for seizure control was presented with severe metabolic acidosis and hypokalemia. Plasma electrolyte and acid-base analysis identified a severe metabolic acidosis (pH 7.153, reference interval: 7.31-7.46), hypokalemia (2.08 mmol/L [2.08 mEq/L], reference interval: 3.5-4.8 mmol/L [3.5-4.8 mEq/L]), and ionized hypercalcemia (1.85 mmol/L [1.85 mEq/L], reference range: 1.1-1.4 mmol/L [1.1-1.4 mEq/L]). Urinalysis revealed a urine specific gravity of 1.021 and a pH of 7.0. Diagnostic workup suggested distal RTA as a cause of the cat's acid-base and electrolyte disturbances. Aldosterone concentration was moderately increased, suggestive of secondary hyperaldosteronism. The metabolic abnormalities resolved with supportive care and discontinuation of topiramate.. Topiramate is suggested to have led to the development severe RTA in a cat.

Topics: Acidosis, Renal Tubular; Animals; Cat Diseases; Cats; Electrolytes; Female; Hyperaldosteronism; Hypokalemia; Male; Topiramate

Topics: Acidosis, Renal Tubular; Anticonvulsants; Female; Humans; Hypokalemia; Incidental Findings; Middle Aged; Topiramate

Topiramate, which is commonly prescribed for seizure disorders and migraine prophylaxis, sometimes causes metabolic acidosis and hypokalemia. Since the effects of topiramate on acid-base balance and potassium levels have not been well explored in children, acid-base balance, anion gap and potassium were assessed in 24 patients (8 females and 16 males) aged between 4.6 and 19 years on topiramate for more than 12 months and in an age-matched control group. Plasma bicarbonate (21.7 versus 23.4 mmol/L; P<0.03), carbon dioxide pressure (39.7 versus 43.2mm Hg; P<0.05), and potassium (3.7 versus 4.0 mmol/L; P<0.03) were on the average lower and chloride (109 versus 107 mmol/L; P<0.03) higher in patients treated with topiramate than in controls. Blood pH, plasma sodium and the anion gap were similar in patients on topiramate and in controls. In patients on topiramate no significant correlation was observed between the dosage of this agent and plasma bicarbonate or potassium as well as between topiramate blood level and the mentioned electrolytes. In conclusion long-term topiramate treatment is associated with a mild, statistically significant tendency towards compensated normal anion gap metabolic acidosis and hypokalemia.

Topics: Acid-Base Equilibrium; Acidosis; Adolescent; Anticonvulsants; Bicarbonates; Child; Child, Preschool; Chlorides; Dose-Response Relationship, Drug; Electrolytes; Epilepsy; Female; Fructose; Humans; Hypokalemia; Male; Potassium; Topiramate; Young Adult