You may experience pain, tenderness, temporary redness, swelling, bruising, firmness, and bumps at the injection sites. Studies have shown that these are usually mild to moderate in nature and clear up on their own in 7 days or less. If you experience swelling at the injection site, you can apply an ice pack for a brief period. You should avoid the following for at least 24 hours after treatment: Strenuous exercise, consumption of alcoholic beverages, and extended exposure to sun or heat.