Botox and other neuromodulators such as Dysport and Xeomin work by preventing contraction of the muscles underlying facial wrinkles such as the "frown lines" in between the eyebrows. These muscles run perpendicular to the wrinkles that they cause, and so it is correct to inject these medications on either side of the line for appropriate treatment. Keep in mind that the results of Botox are often not visible until 5-7 days after injection, and it may take two weeks before you see the maximal effect. In order to receive the best treatment and minimize the risk of complications, I always recommend having injections performed by an expert physician injector. Best wishes,