Which medication is known to increase levels of Lamictal?

Lamictal, or lamotrigine, is primarily metabolized in the liver, and certain medications can influence its levels by affecting liver enzymes. Valproic acid is known to inhibit the metabolism of lamotrigine, leading to increased serum levels of this medication. When valproic acid and lamotrigine are used together, the concentration of lamotrigine in the bloodstream can significantly rise, necessitating careful monitoring of dosages to avoid toxicity.

In contrast, carbamazepine induces liver enzymes, which means it would typically lead to decreased levels of lamotrigine. Oral contraceptives can also alter hormone levels but have a less established effect on lamotrigine levels compared to valproic acid. Sertraline, an SSRI, is not known to have a significant impact on lamotrigine metabolism.

Thus, the interaction between valproic acid and lamotrigine is a crucial consideration in psychiatric practice, making valproic acid the correct answer for increasing levels of Lamictal.