I've got to agree on the Enalapril, my 14 year old Pom has been taking it for several years now. Her symptom was coughing, especially when she was excited. She had an enlarged heart when she was checked at the vet and she's been taking the Enalapril since. She takes it twice a day and it works well for her.

You can get a prescription for it from your vet, since its a people medication and get it filled at a discount pharmacy. I fill it at Walmart and it only costs me $8 a month.