How long will itching and burning persist after cosmetic Botox injections?

It would be extremely rare for your symptoms of itching to be associated with Botox- check with the physician who administered it for sure.There are some patients who do get headaches- they still come back for more though.  I have a handful over the past 10 years- try taking some tylenol before your treatment.  Best to avoid ibuprofen because it can increase the chances of bruising.  

Botox allergy is very very uncommon. It could well be the preservative in the mixing solution or something else. i would contact the treating physician for an examination, guidance and treatment. 

You most likely had some type of dermatitis or skin reaction to either the Botox injections or possibly any topical anesthetic applied prior to the procedure.Please follow up with your provider as soon as possible to let them know what's going on.One word of advice: do not scratch your skin.Any itching or dermatitis will be aggravated by scratching.Most likely this will go away within a day or two if you do not scratch your skin.Sometimes a mild topical anti-inflammatory steroid cream might help.It's important to know what was applied to your skin before and after the treatment to identify what gave you the skin reaction.Best of luck,Mats Hagstrom, M.D.