Good Morning and welcome! I am Dr. Loretta, a licensed veterinarian and I am happy to answer your question.
Something has frightened Duke that you may not be aware of.
This is a common trait in some dogs. They develop fears that cause extreme anxiety similar to those anxieties of humans. The only way to get him over this is "Desensitization" which means constant exposure until Duke realizes that these fears will not hurt him. To do this, first avoid these while making your dog comfortable in his situation. You may need help in doing this since when you try, as you have experienced, he is too afraid to understand. Purchase a DAP Collar at the pet store. This is a canine pheromone that acts as a calming agent and will decrease anxiety.
Thundershirts are useful since this is one of the most common fears causing extreme anxiety and can be very effective.
If this is not enough, your vet will have medication to help him past this. Take Duke to your vet for an exam to be sure there is not a medical cause for this and ask about anti anxiety medication such as Fluoxetine or Buspirone. Then expose him to the things he fears over and over, constantly talking in a soft voice and giving treats
when he does something positive. Here is a site with more tips:
http://www.petplace.com/dogs/fear-of-thunder-sounds-or-noises/page1.aspx.....You will have to click CLOSE WINDOWS to get into this site.
Does that make sense to you?
Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please REPLY so I can clarify for you.
Sincerely, ***** *****