Many women in their late 30s and 40s are diagnosed with anxiety when they are actually experiencing perimenopause. Hormonal fluctuations can cause symptoms like heart palpitations, insomnia, brain fog, and sudden mood changes that closely mimic anxiety disorders. Understanding the difference between anxiety and perimenopause is critical for getting the right support and avoiding unnecessary medication. This guide explains how to recognize the signs, why misdiagnosis happens, and what to do next.