How long should my neck be sore from 4 vials of Kybella? (photos)

I appreciate your concern. While soreness after Kybella is to be expected, yours has lingered for some time. I would schedule a follow-up with your doctor for an in-person assessment before having another Kybella treatment. While it is likely everything is fine, a check is in order to make sure you are not experiencing unusual side effects that need to be addressed. 

Thank you for your pictures and questions. I would go in to be evaluated by your MD injector. While I think it can be normal to have some residual effects for 6-8 weeks, beyond this is abnormal and needs to be evaluated before proceeding with another treatment.Hope this helps!Dallas R. Buchanan, MD, FACSOwner & Board-Certified Plastic SurgeonVIVIFY plastic surgery

Thanks for your question and posting pictures.  We have discontinued Kybella treatments in our practice for melting submental fat.  If you want a non-surgical approach, the FDA recently approved the SculpSure laser for treating submental fat (double chins).  It is a quick 25 minute, completely non-invasive treatment.  In the FDA study, the participants had 100% satisfaction after 1 or 2 treatments.  In the Kybella FDA studies, there is high satisfaction after an average of 6 treatments.  I did SculpSure recently and it was only mildly uncomfortable.  I had no noticeable swelling.  With Kybella, you will have noticeable swelling for 1-4 weeks. 
The treatment cost for 1 SculpSure Submental is less than the average cost of 1 Kybella treatment.  Before you consider CoolSculpting, try holding an ice pack under your chin for 4 minutes.  Now think about doing it for an hour.  You have youth on your side.  I'm not sure that you will need any skin tightening treatments after SculpSure Submental.  Before considering Ultherapy, read the reviews about the high level of pain.  Most patients don't return for their second treatment.  Best of luck.

Very unusual to have "score" neck areas this long after KyBella injections. Best to see the injecting MD for evaluation. I would NOT proceed with second session of KyBella until this issue determined. 

this level of inflammatory response is not abnormal. Though I would've guessed it should be getting better at this point Personally I'm not a fan of this treatment because liposuction is so much more effective, predictable and recovery is much faster.
 With enough time your tenderness will eventually go away. Expect a similar experience for round two. 
 Based on your first picture you had this product injected right over the mandibular branch of the facial nerve. Many people have developed nerve paralysis from injecting in this area causing their mouth to move a symmetrically four weeks to months.  That is an off label use of this product which I don't recommend.

 Best, 
Mats Hagstrom MD