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  1. Animal Health Literacy

Is Your Dog Afraid of Loud Noises? There's an FDA-Approved Drug to Help

Does your dog become a quivering ball of fur hiding under your bed at the sound of fireworks? Do you dread Fourth of July and New Year’s Eve because your dog will try to chew and claw his way through the wall to escape? You’re not alone.

Many dogs have what’s called noise aversion, a sensitivity to loud noises that results in signs of anxiety and fear. One FDA-approved drug, Sileo (dexmedetomidine oromucosal gel), is currently marketed to treat noise aversion in dogs. Sileo is available only with a veterinarian’s prescription.

Signs of Noise Aversion in Dogs
Client Information Sheet
Reporting Problems
Benefits of FDA Approval
More Information

Signs of Noise Aversion in Dogs

Typical signs of anxiety and fear related to noise aversion in dogs are:

  • Panting;
  • Trembling or shaking;
  • Pacing or acting restlessly;
  • Seeking out people;
  • Cowering or hiding;
  • Barking, whining, or howling;
  • Trying to escape, running around, or bolting;
  • Destructive behavior, such as damaging furniture, doors, dog beds, or other nearby items;
  • Freezing in place behavior (being too scared to move);
  • Refusing to eat food or treats;
  • Vomiting or excessive drooling; and
  • Urinating and defecating (having a bowel movement) inappropriately, even though the dog is normally well house-trained.

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Sileo has been shown to lessen the signs of anxiety and fear caused by loud noises such as fireworks. However, it has not been evaluated for noise aversion caused by thunderstorms.

Sileo is a gel that you place in your dog’s mouth between the cheek and gum so that it can be absorbed into the bloodstream. Your veterinarian or trained veterinary staff will show you how to apply the gel. Sileo’s Client Information Sheet also has pictures and detailed instructions.

You should give the first dose of Sileo to your dog at one of three times:

  • About 30 to 60 minutes before the anticipated noise event;
  • When you detect a noise that typically triggers your dog’s anxiety and fear, such as fireworks; or
  • Immediately after your dog shows the first signs of anxiety and fear related to noise aversion.

It takes about 30 to 60 minutes for Sileo to take effect. Your dog should show less intense signs of noise aversion, despite the ongoing noise. Talk to your veterinarian about how to give Sileo to your dog and how often.

Sileo has not been evaluated in dogs with dental or gingival (gum) disease that could affect the drug’s absorption. Sileo should not be given to dogs with severe heart or breathing problems or to dogs with liver or kidney disease.

Oral Dosing Syringe

Sileo comes as an oral dosing syringe which has a ring-stop mechanism on the plunger that must be “dialed” and locked into place to set the correct dose. You must use this special dosing syringe when giving Sileo to your dog.

Accidental overdose can occur if the ring-stop mechanism on the dosing syringe’s plunger is not fully locked. In June 2018, FDA issued a warning about the risk of overdosing dogs with Sileo due to the ring-stop mechanism not properly locking at the intended dose. At that time, there were 54 reports of accidental overdoses. FDA worked with Zoetis, the drug company that markets Sileo, to clarify the instructions on the drug’s label on how to lock the ring-stop mechanism to prevent overdose. Zoetis also created training videos to help veterinary staff teach dog owners how to properly handle and give the gel. Despite these efforts, the problem with the ring-stop mechanism is still occurring, with FDA receiving 34 new reports of overdoses in dogs since issuing the warning in June 2018. 

Signs of a Sileo overdose in dogs include a decreased activity level, sleepiness, sedation and even loss of consciousness, shallow or slow breathing, trouble breathing, being off-balance or uncoordinated, and muscle tremors. 

Veterinarians and dog owners should be aware of the possibility of accidentally overdosing dogs with Sileo if the syringe isn’t properly locked before dosing. It is very important for you to understand how to properly operate the syringe before giving Sileo to your dog. Please report any problems with Sileo’s oral dosing syringe (see section below on Reporting Problems). 

Only adults should administer the gel. Wear disposable gloves when giving Sileo, handling the syringe, or touching your dog’s mouth after application so you don’t accidentally get some of the gel on your skin. Throw out the gloves after each use and then wash your hands with soap and water. If you have cuts on your skin or chapped skin, the drug can be absorbed into your body. If you accidentally get some gel on your skin, you should wash the area immediately with lots of water and remove contaminated clothes.

The oral dosing syringe can be used to give more than one dose. You can use a partially-filled syringe within 4 weeks after first opening it, if there’s enough gel for a complete dose for your dog. Store both unopened and opened syringes at room temperature in the original package, as Sileo is sensitive to light.

Side Effects of Sileo in Dogs

Possible side effects of Sileo in dogs include:

  • Vomiting;
  • Diarrhea;
  • Sedation;
  • Decreased heart rate;
  • Decreased breathing rate; and
  • Pale gums.
Warnings for People about Sileo

Avoid giving Sileo if you’re pregnant, as exposure may cause uterine contractions, decreased fetal blood pressure, or both.

Sileo can be absorbed into your body through your eyes, nose, or mouth. If the drug comes into contact with these areas, flush with water for 15 minutes.

If you’re accidentally exposed to Sileo, your blood pressure may drop. Symptoms of low blood pressure include dizziness; fainting; lack of concentration; blurred vision; nausea; cold, clammy, or pale skin; and rapid, shallow breathing. You may also feel sleepy or sedated and have a slow heart rate. Contact your healthcare provider immediately and bring the package information to your appointment. Tell your healthcare provider that Sileo is an alpha-2 adrenoceptor agonist. Read Sileo’s Client Information Sheet for more information.

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Client Information Sheet

Sileo has a Client Information Sheet that your veterinarian should give you every time you get a prescription for Sileo, whether it’s the first time your dog is receiving the drug or it’s the 15th refill. The Client Information Sheet is written specifically for dog owners, in a user-friendly, question-and-answer format. The handout gives you detailed information about Sileo and its side effects, helping you use the drug as safely and effectively as possible in your dog.

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Reporting Problems

FDA encourages you to call your veterinarian if you think your dog is having a side effect from Sileo. A side effect associated with a drug is called an adverse event. Adverse events also include a lack of effectiveness (the drug doesn’t do what it’s supposed to do) and reactions in people who handle the drug. Call your healthcare provider if you have a reaction to Sileo.

FDA also encourages you to work with your veterinarian to report any adverse event—in either pets or people—associated with Sileo or any product defect such as problems with the oral dosing syringe. How to Report Animal Drug and Device Side Effects and Product Problems.

Remember to keep Sileo in a secure location out of reach of children, dogs, cats, and other animals to prevent accidental ingestion or overdose.

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Benefit of FDA Approval

Knowing a drug is safe, effective, and high-quality is the benefit of FDA approval. During the approval process for an animal drug, the agency evaluates information submitted by the drug company to make sure the drug is safe and effective for its intended use and that the drug is properly manufactured and properly labeled.

FDA-approved Sileo has been shown to be safe and effective in dogs when used according to the directions on the label. The drug is properly manufactured and its label provides dosing and safety information specific to dogs.

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For More Information

See Animal Drugs @ FDA for more information about Sileo.

Contact FDA’s Center for Veterinary Medicine at either AskCVM@fda.hhs.gov or 240-402-7002

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