It's a typical summer evening when the skies suddenly darken and the wind picks up. Within a matter of minutes, lightning is flashing, thunder crashing - and your dog is shaking uncontrollably, urinating in the closet, or ripping apart your favorite pair of shoes.
There is no consoling her until the thunder goes away.
And then the next evening, your town celebrates the Fourth of July with a burst of fireworks, and it happens all over again.
Why do some dogs freak out from thunder or fireworks?
Veterinarians aren't really sure.
"Why are some people afraid of snakes? [Dogs] have the same central nervous system as we do," said Julia Albright, assistant professor of veterinary behavior at the University of Tennessee's College of Veterinary Medicine in Knoxville. "It's not a question we can really answer."
Perhaps the dog had some traumatic incident in the past associated with noise. "Maybe they were stuck outside and the neighbor's kids were shooting off fireworks when they were young," Albright said.
Or it could be genetics. "If we rewind back 100,000 years, big bangs probably meant something very dangerous was making that noise," Albright said.
Or maybe the dog just has an anxious temperament.
Fear of thunder or fireworks seems to vary widely in individual dogs and is not particular to any breed, although large dogs are a bigger problem because their howling is more likely to annoy the neighbors.
Between 20 and 40 percent of dogs seem to have a fear of loud noises, according to Elizabeth Shull, a veterinarian with the Regional Institute for Veterinary Emergencies and Referrals on Amnicola Highway who specializes in behavioral disorders.
A dog's reaction can vary from whimpering and shaking to completely out-of-control violence.
"A severe reaction would be jumping through plate glass windows, destroying the inside of people's cars, tearing out their toenails, or running for miles and miles and getting lost," Shull said. "I have seen dogs that have chewed all the way through drywall, and chewed into metal doors, breaking off their canine teeth."
One factor in a dog's reaction seems to be whether they are exposed to loud noises early in life.
"Some dogs have not been adequately exposed to various sounds at a sensitive time in their life and learned how to assess whether the sounds will be dangerous, and then they get exposed to sounds later and can't learn to adjust to them," Shull said.
There is a window in a puppy's development, between four and 14 weeks, where that needs to take place, Albright said.
But dogs may also be more sensitive to certain things than humans. Dogs will sometimes begin to shake before humans are aware that a thunderstorm is approaching. "Dogs may start to associate a drop in barometric pressure or the static in the air with the noise," Albright said. "Or is there some form of ozone they are smelling. They have a much different sensory world than we do."
Dogs may also be reflecting the feelings of the humans around them. "If the whole family is freaked and anxiety is running through the entire household," the dog may be reacting to that, said Britt Schaffeld, veterinarian with The Animal Medical Center of Fort Oglethorpe.
While cats are also afraid of thunder and fireworks, they are much less of a problem. "A cat goes and hides in the closet. It wouldn't even be on your radar to give me a call for that behavior," Albright said. "But the dog is digging in your closet, destroying shoes and carpet, peeing - cats don't tend to do that."
So what do you do with a fearful Fido? While training may help, medication is the usual answer, Albright said. There are several drugs on the market and a new one, Sileo, which she said should be a big help. New Jersey-based veterinary drug maker Zoetis announced last week that Sileo will be available through veterinarians within about a week.
While the chemicals in Sileo have been used before in other drugs, what is attractive to Albright is that it is applied to a dog's gums and is therefore fast-acting. Pills, which are swallowed, must go through the dog's digestive tract before they take effect, which can take from 30 minutes to an hour and a half, so they are not very effective when an unexpected thunderstorm arrives.
That means dog owners need to give their pets a pill before the storm arrives. "Once a dog is wound up, it is real hard to unwind them," Schaffeld said. "If you know your dog is going to freak out on the 4th of July, then you may need to start on July 3."
But Albright does not expect the new drug to work for all dogs. "Sileo will be a good alternative, but it is not a miracle drug," she said. "There is not a one-size-fits-all drug, either for people or dogs."
In general, the same chemical compounds that work in humans are also effective in dogs. Vets give anxious dogs Xanax, e.g., although in a different dosage. Albright emphasizes that dog owners should not give their pets drugs meant for humans, because the dosages are very different. Talk to your vet to get the proper prescription.
If medication is not immediately available, Albright said dog owners should use common sense to calm their pet. Put them in a closet or bathroom, where the noise is not as loud, and try to get them to play with a ball or eat a treat. Some dogs respond well to pressure or compression vests that hug their body tightly.
But the problem is unlikely to get better without treatment.
"When people call us and are deciding about an appointment, they ask 'Will our dog get used to it, or will they outgrow it," veterinarian Shull said. "Unfortunately, there is a better chance that it is going to get worse if you don't address it."
Contact staff writer Steve Johnson at sjohnson@timesfreepress.com, 423-757-6673, on Twitter @stevejohnsonTFP, and on Facebook at www.facebook.com/noogahealth.