Can Too Much Botox Cause Eyebrows to Drop?

Botox can cause the eyebrows to drop in position especially if too much is injected into the elevators of the forehead. The balance in eyebrow position depends on precise administration of botox into the depressors and elevators of the forehead. If too much botox is placed into the muscles that elevate the forehead, then the net result is a downward or heavy position to the eyebrows often creating the look of a heavy upper eyelid. The opposite can be done if too much botox is placed into the depressors of the eyebrow and the net result can be a surprised or sinister appearing eyebrow. Both can be remedied either by allowing the botox to wear off or by administering additional amounts to the opposite muscles to reverse the downward or upward pull of the eyebrow muscles. This is kind of like a "see-saw" and if one person weighs much more than the other the see saw will land on that side.I hope this helps

The drooping of the brow is a result of the technique or where the Botox was injected.  It will wear off typically before the smoothing effects on the wrinkles wears off.  Well trained Registered Nurses with an appropriate state nursing license, under the direct supervision of a Medical Doctor, who is at the location during the injection, can safely and effectively inject Botox. The nurse should have extensive experience in the treatment, and should have been trained by the Medical Doctor. Spas and Botox treatment centers without adequate supervision can be dangerous. According to state medical licensing requirements, the doctor needs to be on site and immediately available. It is appropriate to ask the person who is going to do the injections about their education, training, experience, licensing, and supervision. A weekend course, inadequate experience, inadequate supervision, or a lack of credentials can be dangerous. If something doesn't add up, go somewhere else!

Botox use in the forehead should be subtle. We prefer a relaxed, not frozen appearance. While the right number of units will vary depending how many horizontal lines a patient is seeking to treat, we find many patients fall into the 8-15 unit range for the forehead alone. A small amount goes a long way here.

Botox can cause heaviness of the brows and upper eyelid areas depending on the patient and injection technique. In a patient with heavy brows or brows that are being constantly held up by the forehead muscles, weakening the forehead muscles with Botox can cause the brows to come down and affect the upper eyelid area. This can often be counteracted by light treatment of the forehead and simultaneous treatment of the glabella and crow's feet areas, as these muscle cause depression of the brow.
Botox can also cause drooping of the eyelid known as ptosis, but this is a different issue altogether and is treated differently. Always see an expert physician injector.
All the best,

Eyebrow drooping after neuromodulators like Botox, Dysport or Xeomin is a rare but well described issue, usually resulting from product placement or the amount used. 
The first thing that needs to be determined is whether it is a droopy eyebrow or a droopy eyelid. Droopy eyebrows are much more common and result from over-immobilizing the only muscle on the forehead that is able to lift up our eyebrows - choosing the right amount and placement in the right patient is key to good forehead results. Droopy eyelids come from the product getting into the wrong muscle that elevates the eyelid. 
Management of them is quite different, but both have strategies to help expedite resolution while waiting for them to resolve with time, and any experience injector should be very familiar with how to deal with them: drops for the eyelids and precise placement of Botox in the brow depressors when it is an eyebrow issue. 
To ensure you are receiving the highest level of care, seek out a modernly trained, new-school dermatologic surgeon, oculoplastic surgeon, facial plastic surgeon or plastic surgeon who is board certified and fellowship trained in one of these "core four" cosmetic specialties. Membership in organizations like the American Academy of Facial Plastic and Reconstructive Surgery help to identify a highly trained surgeon.
Cameron Chesnut#realself500 Physician

Yes, you are describing a feared side effect.  You may be experiencing:1) eyelid ptosis - Botox drifted into the muscle that elevates the eyelid - this can result in the one eyelid looking baggy, and one eye being hard to open all the way.  This is a very uncommon side effect, but it is devastating when it happens.  It will wear away, but can take several weeks.2) eyebrow ptosis - If only your 11's were injected, Botox also affected the the forehead muscle and weakened the forehead.  Your eyebrow position is a balance between your forehead muscle and your brow depressors.  This usually results in a symmetric drop of both brows and the inability to lift your eyebrows very well.  This is a more common side effect than eyelid ptosis, and it too will wear away.

Yes, injecting too much Botox in the forehead can make the eyebrows and upper eyelids appear heavy. The idea is not to be frozen, the goal is to soften your expression lines. Less is more!

Thank you for your question. Neurotoxin injections often do result in an
eyebrow droop. That being said,
injection should only be given by a certified injector. Thorough examination of muscular contracture
should be done before any such injection.
I wish you good luck.

It seems that the aging process is altering the quality of your lids.  Skin does sag and the underlying fat will begin to bulge in the the 40's.  However, Botox may contribute to the low lying appearance of your lids if it is not artfully placed to balance the muscles while allowing you to have motion in the forehead.  The Botox effects will wear off.  Once this occurs you may evaluate your lids to see if a blepharoplasty is desirable to improve the lid appearance.  

Too much botox can definitely over weaken the brow elevator muscles and hence cause the brows to be too heavy and worsen the upper lid laxity.  Some of this can be countered by weakening the brow depressor muscles.  Or you can weight until the Botox wears off as this will also undo the brow heaviness.

Because the frontalis muscle is a brow elevating muscle, injection of Botox into this muscle may cause some depression or "dropping" of the brow. In many cases this may be someone exaggerated during the first few weeks after the injection and usually subsides to some degree.  It is important to note that brow drooping is much different from eyelid drooping that sometimes occurs as a complication of Botox injection and the two issues are treated differently.