The information was quite helpful.
We need to consider this type of cough to relate to three possible sources.1. Heart disease
. Heart valve problems usually occur a little later in life but can't be ruled out. However the cough is usually more persistent, tends to occur more at rest (night in particular) and usually there will be good evidence of exercise intolerence. I think from what you have said we are very unlikley to be dealing with congestive heart failure. But it's important so I need to mention it. Your vet can quickly pick this up witha stethescope at checkup time.2. Throat issues
. Allergic, infective, etc. Usually the cough will be after drinking water or eating and will tend to be a retching type, often with white foam coughed up or swallowed. Seems unlikely here. Not a serious issue and usually clears after a short period even without treatment.3. Tracheal
(windpipe) issues. I think this will be where the problem lies. Classic for small breeds in middle age. The cough is usually brought on by excitement and anything that puts pressure at the thoracic inlet (lower neck)....so pulling on the lead, picking her up, etc. So we will be dealing with either or a combination of tracheitis
and tracheal collapse
. The tracheitis tends to be allergic but can simply be a chronic inflammatory reaction. Collapsed trachea is often involved. This is very common in the small breeds and involves a loss of the circular cross section of the windpipe. The airway collapses easily even when sucking air in quickly (like a wet paper drinking straw....if you can remember what theye were!). Surgery is available for collapsed trachea but should only be attempted if the episodes are very severe.
What should you do? If she is overweight, get some weight down. This reduces the fat in the neck that can put pressure on the trachea. If the lead causes a lot of trouble you can use a chest harness when you walk her.
Anti-histamines can sometimes help. Benadryl Allergy (diphenhydramine)
. Ensure it is not the combination product (Benadryl Allergy and Sinus). Dose at 1 mg/lb. Human cough suppressants are also suitable. Use a young child dose.
A positive diagnosis of tracheal collapse can be achieved by xray although often when the snap is taken the windpipe will be fully open and you miss it. I usually treat with anti-inflammatories or cortisone first.
The lump under her leg. Get it checked. It may just be a lipoma (fatty cyst) but best to be sure.
I hope I have been of help. Please contact me back if I can assist further.
Kindest regards, Peter