On average, results of BOTOX injections can be seen relatively quickly. Most people see results within a day or two, but it can take up to a week for the results to be fully visible. The effects of BOTOX injections usually last about three to four months, with additional injections being necessary for results to be maintained. Because BOTOX injections relax the muscles and prevent them from working at their full capacity, the wrinkles they cause are reduced. Still, this effect usually takes place between three and five days after treatment. It can take up to two weeks after treatment for the full results to be apparent.