Thank you for your patience. There are a few things that could be causing these symptoms in Dude today, and we definitely have to consider an infectious cause here such as Kennel Cough (infectious canine cough) or even canine influenza. Kennel cough occurs due to a number of bacteria and virii, however we generally only vaccinate against the bordetella bacteria and parainfluenza virus. This would typically cause a goose honk type cough and hacking/gagging. Other possible causes for Dude's issue here includes anything from a gastrointestinal issue (perhaps he is actually trying to vomit?), to parasites (hopefully he is up to date with deworming treatments), to less common issues like collapsing trachea (which is rare in young dogs but possible). We even have to consider this could have an allergic basis as dogs do get asthma and allergic rhinitis.
If this just started today, then getting veterinary attention for your boy at some point in the morning should hopefully lead to a quick and easy treatment. If this was kennel cough, then a course of antibiotics may be enough to settle these symptoms within a week. It is better to follow up these issues promptly rather than see if the settle on their own, as often they can be difficult to deal with if symptoms worsen. For now, if you are taking him outside or for a walk, try using a harness rather than a collar, and keep a close eye on his symptoms. If this coughing/gagging/sneezing continues - then you really should get him checked over.
Please keep a close eye on his mucus membranes, capillary refill time and respiratory rate as follows:
Mucus membranes - flip his lip and look at the color of his gums. They should maintain a nice salmon pink color. Get him to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on his gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if he is continuously panting throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
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