I know it depends on which type of SD you have, as far as which muscle(s) the Dr. injects the botox into... AB or AD Dysphonia symptoms are totally different in which muscles in our voice box(es) that produce speach... If you have the AB type, like I do, the side effects of injection (unilaterally)were nothing in my case, even at higher dosage after three shots now in three years. My last shot lasted almost 7 months with no side effects except the slight swallowing thing that happened at first, for about 2 days. Just pay a little more attention to swallowning and tilt your head back a bit, and you will be fine. It's really no bid deal, make sure your Dr. uses the proper scope with the muscle sensor and or camera to see and detect the right muscle and make sure he/she has this extra sensor to detect and inject your specific cramping vocal muscle correctly. The reality is that the results vary depending on each person, which makes it not possible to make this an exact science.
Try voice therapy also. It helps.
Good luck, I have had it, using this treatment.
Speed.
