What is the most serious side effect associated with Lamotrigine?

The most serious side effect associated with Lamotrigine is a life-threatening rash. This rash can potentially lead to Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN), which are severe conditions that can cause extensive skin damage and other complications. The onset of such a rash typically occurs within the first few weeks of treatment, especially when the dosage is increased too quickly. Early recognition of this rash is critical because it can escalate rapidly into a medical emergency requiring hospitalization and significant medical management.

While other side effects like weight gain, kidney failure, and severe nausea can occur with various medications, they do not carry the same level of immediate life-threatening risk as the severe rash associated with Lamotrigine. This differentiates it and underscores the importance of monitoring for skin reactions in patients starting on this medication.