Does Benadryl make dogs sleepy?

I gave my dog Benadryl last night because he seemed to be itching a lot, but since then he's been acting pretty drowsy and less energetic than usual. I’m not sure if this is normal or if there's another reason for his sleepiness. Does Benadryl typically have this kind of effect on dogs, and is it something to be concerned about?

Embark Dog DNA Test

Recommended Product

Your dog's DNA could reveal hidden health risks.

Screen for 270+ genetic health risks and 350+ breeds. Veterinarian developed, research partner of Cornell University.

$199 USD
$139 USD
Save $60· Free US Shipping

Answer

Benadryl can cause drowsiness in dogs, which is a common side effect that many pet owners notice after administering the medication.

  • Drowsiness or lethargy after administration
  • Reduced activity levels or increased sleep
  • Occasional mild gastrointestinal upset

It's important to monitor your dog's response to Benadryl and consult with a veterinarian if you have concerns about his reaction. Although drowsiness is typical, each dog's reaction can vary, and understanding why it happens is key to ensuring your pet's comfort and safety.

If you have further concerns or notice unusual symptoms, please book a consultation with one of our veterinarians at Dial A Vet.

Frequently Asked Questions

  • Is drowsiness a common side effect of Benadryl in dogs?
    Yes, drowsiness is one of the most common side effects of Benadryl in dogs. It is similar to how people might feel slightly sleepy or lethargic after taking an antihistamine.
  • How long does the drowsiness from Benadryl last in dogs?
    The drowsiness typically lasts for a few hours, depending on the dose and the individual dog's metabolism. If it persists or your dog seems excessively lethargic, consult your veterinarian.
  • When should I be concerned about my dog's reaction to Benadryl?
    If your dog experiences symptoms that are severe, unusual, or persisting much longer than expected, such as extreme lethargy, vomiting, or respiratory issues, consult a vet immediately.

Clinically Approved Standard by Dial A Vet Veterinary Team

Disclaimer: The customer and expert messages presented herein may have been altered with artificial intelligence or modified to enhance readability and safeguard the privacy of individuals. This content is for informational purposes only and is not a substitute for professional veterinary advice, diagnosis, or treatment. If your pet is experiencing a medical emergency, contact your local veterinarian or emergency animal hospital immediately. Talk to a vet now.

Embark Breed + Health Dog DNA Test

Recommended for Dog Owners

Embark Breed + Health Dog DNA Test

18,899 Reviews

The most comprehensive dog DNA test. Screen for 270+ genetic health risks and identify breeds from 350+ breeds, types & varieties.

$199$139Save $60

Free US Shipping · Veterinarian Developed

Next available appointment

Loading…