Q. Why do I experience heart palpitations and insomnia after taking herbal diet medicine? I'm wondering if these are side effects.

Herbal diet medicine focuses on maximizing metabolic efficiency. From a Western medical perspective, it stimulates the sympathetic nervous system to raise the basal metabolic rate, essentially tricking the body into an 'exercise mode' even at rest. As heat is generated and fat begins to burn, reactions such as palpitations, sweating, or mild tremors naturally occur. Traditional Korean Medicine (TKM) interprets this as the active circulation of Qi (vital energy) and the generation of Heat. In patients with a Spleen Deficiency (脾虛) constitution, metabolic waste known as Phlegm-fluid (痰飮) tends to accumulate. When the medicine aggressively promotes circulation to expel this Phlegm-fluid, those with insufficient underlying energy may experience temporary insomnia or chest tightness as their body struggles to keep up with the rapid change. Furthermore, if there is significant Blood Stasis (瘀血)—stagnant blood impurities—the sudden increase in circulation speed may cause headaches. These symptoms are generally a sign of a temporary 'overload' occurring while the medicine forces a dormant metabolism to restart, rather than a sign that the medicine is inherently harmful. The core of TKM weight loss is finding the balance where Phlegm-fluid and Blood Stasis are removed without depleting your original Qi. If the discomfort is bothersome, the best approach is to slightly reduce the dosage to give your body sufficient time to adapt to the increased metabolic state.