How to calm my dog's anxiety of loud noises?

I have a 3 and a half years old golden retriever. She is terrified of any loud noises such as thunder, lawn mowers, garbage trucks coming down the street, or airplanes and jets flying over our house. When she hears these loud noises, she starts shaking really bad and whimpers a little bit. She weighs 60 pounds so you can't hold her. I bought a ThunderShirt which helps with her separation anxiety, but not with her anxiety of loud noises. Her vet gave me some medicine for her to take that calms her down, like it makes her sleep; it makes her in a groggy, drowsy, drunk state so she doesn't care about the noises. But, her vet advised me that her taking this medicine all the time is not good for her health, and I don't like to give the medicine to her either because it makes changes in her behavior. I've also tried to drown the noises out with music, but that doesn't work either. So, does anyone have any drug-free solutions to calming my dog down when she hears these loud noises?