Skin-Booster Injection on the Left and Right Sides: Which Side Is More Painful?

Skin booster injections using agents such as hyaluronic acid and poly-D,L-lactic acid (PDLLA, Juvelook, VAIM GLOBAL Inc., Korea) are commonly used to enhance skin texture and reduce wrinkles. However, pain during injection remains a limiting factor in patient compliance and comfort. To evaluate whether there is a difference in perceived pain between the left and right facial sides during PDLLA skin-booster injections. Twenty Korean patients (13 females, 7 males; aged 22-67) received intradermal PDLLA injections in both cheeks over four treatment sessions at three-week intervals. Pain intensity was recorded immediately after each injection using the visual analogue scale. Differences in pain perception were analyzed by side, sex, and age. The left side consistently showed higher visual analogue scale pain scores compared to the right side (p < .05). While males initially reported higher pain levels than females, this difference attenuated over repeated sessions. No significant correlation was found between age and pain perception. PDLLA skin-booster injections are perceived as more painful on the left side of the face, possibly due to right hemispheric dominance in pain processing. Recognizing such lateralized pain responses may enhance patient comfort and inform clinical practice. Further studies with larger sample sizes and consideration of injector handedness are warranted.