History of Anaphylactic Reactions - Safe to Get Botox?

True anaphylactoid type reactions to Botox are rare and should not be a concern, However, I would discuss this with your allergist.

If your anaphylaxis is an allergic reaction to one allergen, it does not mean that you would develop an allergy to another, yet many people with allergies, are in fact allergic to several antigens. Clincially, the risk of an allergy to Botox is extremely small. You may be able to find an allergist that will do a skin prick test to the botox solution (the dermatologist or plastic surgeon who you plan on having inject you with the Botox would have to provide the allergist with the solution if the allergist could not acquire it themselves from Allergan, the company).

It is very, very unusual to have a reaction to Botox - even a minor reaction.  With your history of major anaphylaxis reactions with unknown cause, it would be important that you have a complete evaluation by an immunologist prior to any injections or new medications.  If with this, you would need to carefully consider the risks and benefits of any treatment.  Good luck.