Red, itchy, swollen eyes reaction to Botox, what is going on?

There are a few possibilities.
1. true but very rare allergy to Botox itself
2. allergy to a preservative in preserved saline liquid used to dissolve the Botox. Many use this solution but it may be that if this is the case, that using non-preserved sterile saline would work for you.
3. allergy to a disinfectant used prior to the injections but as the eyelids are swollen it's doubtful that the disinfectant touched that skin as the Botox is usually injected outside of the eyelid area.
An allergist can help shed more light on your situation.
The information provided in Dr. Shelton's answer is for educational purposes only and is not intended to constitute medical advice.  The information provided should not be relied upon as a substitute for consultations with a qualified health professional who may be familiar with your individual medical needs.
The information provided in Dr. Shelton's answer is for educational purposes only and is not intended to constitute medical advice.  The information provided should not be relied upon as a substitute for consultations with a qualified health professional who may be familiar with your individual medical needs.

While allergies to Botox are extremely rare, it can happen. If this persists, I recommend following up with your injector. Hope this helps.

Botox allergies are extremely rare, however, this is difficult to answer without an in-person evaluation. Botox results take 1-2 weeks and can be softened with venus legacy and thermage treatments. See an expert. Best, Dr. Emer

Thank you for your question. Botox is a purified protein used to address wrinkles associated with facial expression. When injected into the skin Botox will relax the muscles and smoothen out the overlying wrinkles. The most common areas of treatment are in the upper face. These include the horizontal lines seen on the upper forehead when one raises the brows, the vertical lines seen between the brows when one frowns (frown lines), and the crow's feet seen around the eyes when one smiles. It is difficult to make an assessment without a formal exam where the entire medical history is reviewed. 

Thanks for your question.  A true allergy to botox is possible but very rare.  I would suspect that other products used in the procedure such as the sulfite preservative in the saline, latex gloves, or skin prep solution may be the source of the allergic reaction.  Since this is the second time, I would consult an allergist to avoid worse reactions in the future. Once you have identified the issue, you should be able to make some minor changes that will allow you to continue using NT in the future. Also, you can consider other similar products such as dysport.  Best of luck.