Any needle stick can cause bruising. Juvederm and Restylane can bruise more readily than other fillers as a consequence of their chemical properties, yet most patients don't bruise much. You can help minimize bruising by not consuming blood thinners such as aspirin for two weeks before injections, avoid the non-steroidal antiinflammatory agents such as: Motrin, Ibuprofen, Advil, Alleve, Naprosyn, and others, for three days before, and avoid Garlic, Ginseng, Ginko Biloba, Fish Oil and Vitamin E supplements for two weeks before. Slow delivery and gentle pressure by the doctor helps minimize bruising and ice packs for a minute or so after may minimze bruising. Some doctors believe in Arnica Montana and Bromelain herbal supplements that can be taken before during and after the treatment to minimize bruising. Do not work out right after as exercise or increasing the blood pressure (bending over as an example) can increase bruising. If you do all the same each time, you still might find that sometimes you will bruise and others, not. Good luck.