There is increased risk of bleeding and bruising when the patient has consumed alcohol prior to being injected so that should be discouraged. Informed consent, which is required for medical procedures, also needs to be done while the individual is sober. Allergic reaction is very rare but certainly possible! Certain protocols are required to treat an allergic reaction and usually an office environment is required to keep these tools and medications. Other common side effects like ptosis (eyelid droop), undesired numbness or paralysis, facial asymmetry, etc. will not show up until the product has kicked in. This can take several days to weeks to be at full effect. These mainly result from the technique used or if post-procedure instructions are not followed. However, if the injector is distracted (like at a party) then they are more likely to make a mistake causing one of these effects.