Thank you for the additional information.
I am sorry to hear that Aby has been coughing lately. Kennel cough is a possible cause as this disease is very contagious between dogs. Even if she has not been around other dogs she still could get this disease as it is an airborne disease. Without examining her, determining the exact cause will be difficult though I can tell you some of the disorders other then kennel cough that causes a cough in a 12 year old dog:
- Heart disease
such as a weak valve or valvular disease
- A collapsing trachea which is common in smaller breed dogs - this is basically where the trachea is made up of a very flimsy cartilage that folds or collapses when she is breathing faster
- Allergic bronchitis
- Mild pneumonia from bacteria or fungal infections
At this time the best way to get an exact diagnosis would be to take Aby to your vet to have an exam performed. Your vet will most likely also want to take an x-ray to get a better diagnosis of where the cough is coming from. I do not think that you need to rush to the vet tonight unless Aby starts to really have labored breathing or becomes very lethargic, but I would consider taking her to the vet soon.
Your vet will be able to give her some medications to stop or reduce the cough based on the exact cause. For now if you wanted to give her something you can use some Robitussin DM
very safely. The dose for dogs is 1/4 of a teaspoon for every 10 pounds every 8 hours. This can cause some drowsiness but is otherwise very safe.
Hope this helps to answer your question - if not or if you have any more questions please feel free to reply by clicking on the "reply to" button. Thank you for your question!