Dear Morgan:Acute swelling of the hands is most likely angioedema. This can have many causes including an unusual reaction to the albumin in the Botox prep or a preservative in the saline used to diltute the Botox, and of course can be due to a myriad of other agents unrelated to the Botox treatment. You should see your provider while you have this symptom to determine if it is indeed angioedema, and then to be evaluated, if necessary by an allergist, to determine the cause.In any case, it will be possible for you to have treatment in the future by using a different botulinum preparation and using a preservative-free preparation if necessary.All the best,Dr. Clark