Need More Botox In Forehead After 6 Weeks, Shouldn't It Last Longer?

Thank you for your question and concern. I train a lot of injectors in the proper technique for Botox injections. Here are some of the common reasons that Botox wears off too quickly:1) Inadequate dose - higher doses usually corrects the problem2) Cookie cutter approach to injecting Botox. The same technique is used for every patient and it works for most, but not all patients. The cookie cutter approach fails to appreciate the differences in anatomy of the facial muscles that can vary by the individual.3) Rarely, there are patients who truly have shorter durations with Botox and may want to consider the different neuromodulators available to see if there is a difference. It sounds like you might want to consider trying slightly higher doses, but becareful not to be too aggressive as you may develop a heaviness in the brows.  I would recommend that you go an experienced board certified plastic surgeon or dermatologist who does a high volume of injectables to discuss your experience in more detail.

Like many other areas of the face that are treated with Botox, results last about 3-4 months for the forehead, or possibly a little longer. However, in general, it's better to be a little less aggressive when treating the forehead to prevent the risk of drooping, particularly since you are a "first timer". You may have received fewer units so that your reaction to treatment could be gauged first. 

There are many individuals that can not have all of the forehead treatment without concern of the forehead dropping and affecting the eyebrow and even eyelid position if this phenomenon of forehead sagging had already occurred.  These individuals need some function of the forehead to be left intact after Botox to avoid this drop as the forehead helps lift those areas.  Keeping this in mind, the physician tries not to inject those danger areas but then partial treatment may induce compensatory over contraction of other areas and the outer eyebrows may get lifted. With this nearby contraction, possibly your botox is wearing off more quickly. The company's insert does state 8 to 12 weeks for glabellar frown lines longevity of Botox effect. Six months is not seen clincally for the vast majority of patients. I typicaly see 12 to 16 weeks of duration. You might need more units than you had but they must be in the correct areas to avoid the droop and the glabella between the eyebrows probably has to be treated to help lift the forehead while treating the forehead for its horizontal creases at the same time as the forehead could drop.