Q. My Chihuahua keep coughing for two months now
A. Cough is a symptom that something is wrong and if is been coughing for 2 months should be activating the alarm bells! Dogs can cough for different reasons but mainly are respiratory problems or heart disease. Is more likely to be heart caused if happens more during the night and the dog looks tired or refuses to do exercise. Also can be cause by lung parasites and that's something we can prevent using a proper worm treatment. De-worm your dog and if the cough is persisting go to your vets for a proper check up.
A. You need to take it to see a vet, 2 months is quite a while. It could be a heart or respiratory problem that could be improved with medications. It could also be worm related.