What are the side effects of hyaluronidase?

All of the panel members offered a broad range of valuable feedback. However, in reading the original posting, it would appear that possibly the product was not placed under the muscle in the second treatment. Although hyaluronidase was used to dissolve the product, unless it was placed exactly where the filler was placed, it will not offer much benefit. This may account for why you are describing being able to still feel the filler product but have "bags" of fluid above it. You may also be creating a vicious cycle by self-treating in an effort to find a resolution. Because this is a delicate area, you may be aggravating the condition.
I would agree that you should be evaluated by a physician that is familiar with injectable fillers for tear trough procedures. The last panel member mentioned that this does not mean you should go to a nurse at the local medspa. While this may have been well-intentioned advice, it certainly does a disservice to registered nurses and assumes also that it was a non-physician that performed the treatments that resulted in a negative outcome.

It is important for you to know if it was a true allergy to hyaluronidase or just excessive bruising.
You mention the word -black along with the swelling hours after hyaluronidase injection. Please tell me if you got a lot of bruising. If you did then it is possible that what you have described is prolonged lower lid edema after excessive ecchymoses (bruising).
If you can describe the situation in more detail with some photos from after the hyaluronidase injection (same day) that would be helpful.
At this point, watchful waiting and letting the eyelids heal is the best thing you can do.
Please keep us posted.
Regards

Hi Tried Aussie,
The puffiness and swelling will resolve with time. The edema is not permanent and the hyaluronidase has not done irreparable damage. I have treated a few patients with similar scenarios, and eventually their lower lids returned to normal. You do need to be patient. The most difficult thing to do is nothing. It may take weeks to months.
Do follow the good doctor's advice here on RealSelf.com and see a board certified opthalmoplastic surgeon, facial plastic surgeon, or plastic surgeon who has experience with injectable fillers in the lower eyelids.
Once again, in the future, I would recommend using Restylane in the delicate lower eye lid area as sometimes Juviderm is a little too hydrophilic (attracts too much water from the skin) and swells too much.
I hope that your eyelids return to normal very soon.
Dr. P