So she had issues with noise when you got her so it would stand to reason a buzzer might set her off as well. What you will have to do is desensitize her to noises you can control unlike a thunder storm which cannot be controlled. I would try lowering the sound if possible and gradually making is louder or if you cannot control the volume then take a recording of the noise so you can control the volume. You will want to start off low and gradually increase the sound and do this when you are playing with her. I found it helpful to play a sound all day long on a low set volume so the dog could hear it but it was not interfering with everyday routine. This way it becomes normal to the dog.
I don't find tranquilizers to be very helpful for thunderstorms as the dog usually knows they are approaching long before the human does and is already stressed over it. What I would try for anxiety is over the counter melatonin as this can be given morning and night on a daily basis. The thunder shirt too, works for some dogs and not for others.
I would do some positive reinforcement training with her on a daily basis to boost her self esteem which in the end also helps her to stay focused on you rather than what is scaring her. Clicker training works well but if the click sound is too loud for her then as a marker use your voice, one word, such as yes, as the maker cue. Reward with special treats such as hot dog slivers.
Below you will find instructions on clicker training and for melatonin dosing.
Many organizations now train service dogs for PTSD so I would also look into that for yourself. There are places where volunteers raise and train the service dog for two years and then that dog goes to someone in need. You just have to apply for the dog.
Clicker training/positive method training/ print off
video’s to see how clicker training is done, scroll down to videos http://www.clickertrainusa.com/clicker-training-videos.htm
Melatonin found in drug stores by vitamins
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