Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
I am so sorry to hear Lucy is coughing. It sounds like she might have been exposed to Kennel Cough (CLICK HERE), often at a puppy daycare, boarding, grooming, or dog park but even can have exposure on walks.
Unfortunately even if vaccinated for kennel cough, there are many strains and exposure or even the modified live vaccination itself can still result in kennel cough in puppies and adult dogs. Similar to having a flu vaccination but still getting the flu virus in a more mild form. The cough is comparable to something being caught in the throat or a cat with a hairball.
There are some home remedies that can help reduce the cough and give relief
1.) The steam of the shower when the cough is severe or constant
2.) A little honey three times daily can help soothe the lungs
3.) If you have a humidifier or nebulizer that would also be wonderful to use in this situation
Unfortunately I prefer to avoid cough suppressants because when suppressing a cough if there is phlegm or buildup and lead to bronchitis or even pneumonia if the material is not coughed up so this is not something I tend to administer.
I hope this information makes sense! If the cough becomes productive again I would advise a veterinary exam to ensure antibiotics are not warranted. In addition if there is development of lethargy or a reduced appetite then it would be best to have a veterinary exam.
Please let me know if I can be of any further assistance to you both!
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