Severe asymmetry with eyebrows. What can be done?

Thank you for your question. You are correct that asymmetry is normal. No facial features can be perfectly asymmetrical through genetics alone and even with facial plastic surgery. Many patients often combine a brow lift and an eyelid lift because the surgeries are complementary especially when performed at the same time, and more efficient for recovery time and costs of surgeries, operating room time and medications. I suggest that you move forward and consult with a board certified facial plastic surgeon.
Best wishes,

You likely have left upper eyelid ptosis, causing the left eyebrow to raise in order to assist lift the droopy eyelid. See an oculoplastic specialist for eyelid ptosis evaluation. See following link.

without any medical causes can be addressed with Botox on the forehead on the high side to see if that brow will drop a little.  If you like the left side better, then a little Botox under the arch of the right brow may allow it to ascend enough to make the asymmetry less appreciable.  And if you want more of the sure thing, then a unilateral browlift on the right side should do it for you BUT perfect symmetry is still unpredictable and all that can be guaranteed is that your right brow will be higher and your natural asymmetry less.

Thanks for the photo. Some asymmetry is common. If the excess arching on one side and higher position of the peak of the brow causes you concern, three common approaches may be appropriate:1. Have Botox performed to try to slightly lower the higher side by asymmetrically treating the high side's frontalis muscle more than the lower side. Doesn't sound like you would like this idea since you prefer the higher side.2. Try to raise the lower side with treatment of the brow depressors - this usually is only helpful if the goal is to raise the outer, arching area of the brow, not the whole brow itself.3. Have an endoscopic browlift performed to raise the lower side to correct its position.By the way, I doubt you actually have a droopy eyelid. More likely, you have brow ptosis (drooping of the forehead) which causes forehead tissue to descend down onto the upper eyelid tissues, making the eyelid look heavier.

The forehead anatomy is complicated, but basically is composed of both elevator and depressor muscles which appear to be slightly out of balance as noted in one single photograph.  Botox offers a temporary improvement to the asymmetries of the eyebrows,  A surgical browlift can help address the asymmetries permanently.  An asymmetrical amount of skin is removed on the lower side, the muscles are weakened on the more active side  to make the eyebrows more symmetrical.  There is no perfect facial symmetry.  For many examples, please see the link and video below