Can Botox under the right eye cause cheek drooping?

Thank you for your question.  Botox works by weakening the targeted muscles.  If the product is inadvertently injected into a muscle that elevates the mouth/cheek, i.e. your smile muscles, then it might cause a change in your smile or possibly a droopy look to the cheek.  I have seen this in patients who come and say they had Botox for their crows feet or under their eyes.  I would recommend that you visit with an injector who is very well versed in the underlying anatomy and experienced with Botox.  I train a lot of other injectors on how to inject Botox and fillers and am quite surprised by how much time I need to spend on teaching anatomy and what can go wrong if we inject too low, high, deep or superficial in a given area.  Facial muscles are quite small and reside in specific layer of our facial tissues so the more precisely we can deliver Botox, the more likely you will achieve the desired result.  Best of luck.

Thank you for sharing your question.  If Botox is placed too low along the eyelid it may affect the muscles of the face responsible for maintenance of cheek position and lip elevation.  Be sure to see an ASPS board certified plastic surgeon in order to minimize these complications. 

If injected in the wrong area and at the wrong depth, Botox can certainly cause paralysis of muscles in that region that can give the appearance of a cheek droop. This is one of the reasons why I feel going to a board certified plastic or facial plastic surgeon is important, even though it's "only Botox". 

An intimate understanding of facial anatomy is necessary in some cases, and surgeons are the best trained to know the anatomy, especially in regions such as the lower eyelid.