Any signs of Pain?
Any strange head carriage?
Any light sensitivity?
Any heavy exercise recently?
How long has this been going on?
I hope I can help.
The dog shows no sign of pain, the head carriage is normal, no light sensitivity, and no heavy exercise. He is an English Labrador retriever, weighing about 95 lbs. I have been out of town the last two weekends, and he had been overnighting at his favorite daycare. I do know they have small pools, and much activity all day long. The surface is also concrete. Usually he goes to day care once every two weeks, other days he comes with me to the barn where he plays with two other labs, and I will trail ride my horse with the three following me.
Since I have had him, I have always cleaned his ears every Sunday, he has never had an ear problem. Unfortunately, being gone the last 2 Sundays, I assumed that my huisband had been treating the ears, he had not. This past week I noticed the dog showed no interest in playing, retrieving etc. I also cleaned his ears and discovered that there was the brown substance in the inner ear, but no odor and discharge. Today, I had the feeling he lost his hearing, and he is reluctant to go up steps, he never really enjoyed steps, but now he would prefer to avoid them.
I made up an ear solution from a recipe of a dog owner which contains vinegar, boric acid, alcohol and betadine antiseptic solution. I have just started using it, as the store bought solution, (aloe based) had run out.
I am not a big fan of putting rubbing alcohol in an ear if it is inflammed, so I would hesitate to use this the home remedy. This could certainly thrust him into a lethargic periods. If this started prior to using the home remedy, then the ear infection could be the reason for the behavior. In many cases, it takes more aggressive therapy such as topical antibiotic, or oral antibiotic.
Other issues are behavioral (especially if he is attached to you and you were gone), orthopedic soreness (I would expect to see limping), upset stomach etc.
I would continue to watch him. IF you notice any signs of bloating abdomen, pale inner lip and gums, stumbling or collapse, then a more immediate vet visit is warranted.
To help any potential upset stomach, you can give a tablet of pepcid AC or tagament twice daily. This will help reduce the amount of stomach acid produced which may help perk him up. It is worth a try as it will not hurt anything. I hope this helps and gives you direction.
If your vet diagnoses an ear infection, I would not be surprised if an antibiotic were used. Another possible reasons for lethargy could be an underactive thyroid, which generally cause weight gain, lethargy, poor coat etc, but all signs are not always present and this is relatively common in labs. Your vet may run bloodwork to rule this and other issues in/out. I hope this helps.
I cannot prescribe prescription medication over the internet, but this could be one of the oral forms your vet could use, but there are other possibilities as well. The mentioning of the thyroid disease was more of a FYI in case your vet found something unusual on physical. I am trying to throw as much out there as I can so you are not surprised. These are very vague signs, so there are many possible issues. I hope this helps.