The Bordetella vaccine is not 100% protective, unfortunately. Also, the protection it confers starts to wane after about 6 months, so my guess from what you are describing is that your dog does indeed have Kennel cough
Let me explain...
Kennel cough (Bordetella, infectious tracheobronchitis) is a highly contagious cough that is transmitted by saliva or through an aerosol when a dog coughs. With kennel cough, dogs have a cough that sounds like something is stuck in their throat, and after coughing a few times they have what is called a "terminal gag" which means that they sound like they are bringing up phlegm.
If you watch closely, you will often see dogs swallow after this final gag - they are in fact swallowing phlegm. Some dogs will even cough up a puddle of clear, whitish, or slightly yellow mucoid fluid.
Kennel cough is highly contagious so dogs that have this should be kept isolated from other dogs for 2-3 weeks until it resolves.
Most cases resolve without medications, but in some cases patients are put on antibiotics and/or cough suppressants.
Antibiotics are used in dogs who are at risk for a secondary pneumonia (very young or very old dogs, or those with a suppressed immune system).
Cough suppressants are used when the cough is so severe that the dog cannot sleep. There can be quite a bit of phlegm with kennel cough, and it is better that the dog DOES cough that up, rather than leave it in the lungs by suppressing the cough. However, there has to be a balance where it's possible for the dog and his human companions to sleep.
For dogs that are unable to sleep, I do sometimes advise owners that they can give Robitussin DM
. It is very important to read the label carefully and find a cough medicine that contains ONLY dextromethorphan (DM). This can be given to dogs.
Here is more about precautions and dose:
Watch your dog to see if she is retching or gagging at the end of her coughing episode. If she is, or if she is coughing up puddles of phlegm, she likely has kennel cough.
I'll give you links to further information:
If she coughs up fluid that is green, or is blood-tinged, or she is lethargic or has difficulty breathing, then you should definitely see a vet.
Many dogs with Kennel Cough seem to have a sore throat and thus don't want to eat their dry food. You can soften it with warm water to make it easier to swallow. Keep your dog isolated from other dogs for at least 2 weeks! Keep her as quiet as possible - just out for potty breaks and back in. Kennel cough usually gets worse for 2-3 days, then frequent coughing with phlegm for 2-3 days, then starts to slowly get better.
It is also helpful to walk dogs with Kennel cough on a head halter or chest halter, as a leash around the neck can pull on the trachea and start a coughing spell.
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If you need more information, just click on reply and I will still be here to answer further questions!
The above is given for information only. Although I am a licensed veterinarian, I cannot legally prescribe medicines or diagnose your pet's condition without performing a physical exam. If you have concerns about your pet I would strongly advise contacting your regular veterinarian.
Best wishes to you and to your dog! Fiona