Topiramate

Question 1

Use

Answer 1

Topiramate is used in epilepsy and in bipolar affective disorder as a mood stabiliser. It inhibits voltage gated sodium channels, therefore suppresses action potentials. In addition it increases GABA levels.

Topiramate is unusual in that its use is associated with weight loss (most psychotropic drugs are associated with weight gain).

Question 2

Side effect

Answer 2

Topiramate can cause metabolic acidosis secondary to inhibition of carbonic anhydrase. This can lead to the development of calcium phosphate nephrolithiasis (renal calculi aka kidney stones).