There are several types of dermal fillers and a range of different formulations in the collection which you can find out more about here.
There are a few things that you can do to help ensure that your skin is ready for your dermal filler treatment. This includes not drinking alcohol for 2-3 days prior to your appointment, this helps to lessen your risk of bleeding and bruising. It is also advised that you avoid consuming garlic, fish oils, ibuprofen and aspirin for 1 week prior to your appointment as these can all thin your blood making bruising more likely.
It is also good if you have had plenty of rest the night before treatment so you arrive to your appointment feeling calm and relaxed.
Bruising and swelling post dermal filler treatments are always going to be a risk and where you can take steps to avoid these, you should always be aware that it could still occur if you are prone to bruising.