# Cutaneous Pseudolymphomas of the Scalp Secondary to Lamotrigine

## TL;DR

A 25-year-old woman developed scalp nodules linked to lamotrigine, which resolved after stopping the drug, suggesting a rare but reversible drug-induced condition.

## Contribution

This case highlights lamotrigine as a potential cause of cutaneous pseudolymphoma, a rare and reversible drug reaction.

## Key findings

- Scalp nodules resolved after the patient tapered lamotrigine.
- Biopsy showed mixed B-cell and T-cell lymphocytic infiltrates.
- Switching to lurasidone led to complete resolution of the lesions.

## Abstract

We present a case of a 25-year-old woman with bipolar disorder that developed five asymptomatic, enlarging scalp nodules over nine months while on a stable dose of lamotrigine. A biopsy revealed mixed B-cell and T-cell lymphocytic infiltrates, and after self-tapering the medication, the lesions shrank. The patient was switched to lurasidone, leading to complete resolution of the scalp nodules. This case supports lamotrigine-induced cutaneous pseudolymphoma, a rare but reversible condition, and emphasizes the need for clinicians to consider drug-induced pseudolymphoma.