Can you get a brow lift for just one side? My right eye has always been saggy. (Photo)

As we age, our eyelids naturally sag and droop. A combination approach would be best to see visible improvement. In terms of non-surgical treatment options, I would recommend a Chemical Brow Lift (using Botox, Dysport, Xeomin, or Jeuveau) and filler injections to rejuvenate the temples, eyebrow, eyelid, eye troughs, upper eye hollows, and forehead. I typically combine this with Ultherapy and thread lifting to lift the brow; RF and skin tightening laser treatments to stimulate collagen production and rejuvenate the skin; and laser or superficial RF devices for improvements in texture, color, and any crepey skin around the eyes as needed. In some cases, surgery is the best solution to achieve the desired results. See an expert for a formal consultation. Best, Dr. Emer.​

Hello nfrancThe best way to find out if a brow lift is right for you is to consult with a board certified plastic surgeon. The surgeon will examine your skin, including its texture and elasticity, and evaluate the tone of your underlying facial tissues and bone structure.

Thank you for your question. Yes, you can consider a brow lift procedure. I suggest that you move forward and consult with a board certified facial plastic surgeon.
Best wishes,

Botox can lessen the difference as others have mentioned
A one sided endobrow lift is the most direct solution. 
However, with either, if the right eye ball sits deeper than the other side, or if there is some asymmetry in the orbital bones you might expose another feature of asymmetry.
There are fixes for that that you may or may not want to explore but you should be aware of that possibility.

It is possible to perform a one-sided brow lift. There are variety of techniques and placement of incisions to accomplish your goal. You might also try Botox on the higher side