Facial hair loss after 1 IPL treatment -- will my hair grow back?

In my experience hair does grow back after IPL treatment since IPL is not the best treatment for hair removal, so if you had hair lost after IPL it will generally come back. A couple options to try, (since you are concerned about the patchy hair) while you wait for the hair to grow back as it may still take several months is to try Latisse off-label in that area and just use Latisse, obviously it is used for eyelashes you can apply a little bit in that area and you will notice some hair growth in that area. 

I used IPL RF for my son's acne, his beard is patchy even years later, but his skin looks great. You could try a hair growth serum or even Latisse to help grow back the areas. Only use Latisse where needed, Latisse is usually over $100 for a small tube, but works very well. It may take several with daily usage. There is different settings on the machine, but IPL goes after color, if your beard has color it will still heat up the hair and follow to the follicle, you are seeing damage to the follicle. Don't despair, I would purchase a hair growth serum. 

Thanks for the question and I'm sorry to hear about your experience.  IPLs generally cause hair reduction and are not thought to result in permanent hair loss.  I have seen patients that develop a patchy appearing beard after being treated with IPL for something other than that purpose by other providers(they didn't want hair removal).  For that reason I generally recommend using either a V Beam or Xeo laser for redness.  These types of lasers should not affect hair growth or regrowth.

IPL works great for rosacea but it can singe hair. For men there is always a risk for some hair thinning afterwards.
The good news is that the setting used for rosacea is different than the one for hair removal which means your beard will grow back but it might take time. You need to be patient. In case you are considering having more IPL sessions make sure the beard area is covered so the beams from the IPL do not reach your beard.
Good luck.

I'm so sorry you are going through this. Unfortunately, depending on hair color (darker is more affected) and skin color (paler is also more affected), IPL can be used as a very effective hair removal device. Complete hair removal usually requires multiple sessions, but even a single session can, and often does remove some of the hair.Once this has occurred, options are unfortunately a bit limited, but some male patients can have hair regrowth using PRP and other regenerative treatments - this is usually most effective if you start treatments shortly after the initial injury.