My dog has congestion and mouth breathing. Can I give Benadryl?
Hi there! You can give him some benadryl (diphenhydramine) at 1 mg per pound. The tablets usually come in 25mg. You can go a tad higher too and it usually won't hurt anything. For example, if the dog is 10 pounds, I'll just have owners give 1/2 of the 25mg tablet which comes out to 12.5mg, or if the dog is 5 pounds, then 1/4 tablet which is 6.25 mg, etc. If your dog is really small, you can pick up the children's benadryl and use that to get a more accurate dose.
The benadryl may or may not help, but it can't hurt. I think it's worth a try until you can get him in to see his veterinarian again. I would have him seen though since he has started medications and it still seems to be getting worse.
Just be sure to check labels and make sure the only ingredient is diphenhydramine (or diphenhydramine hcl). Some of the benadryl products can have pseudoephedrine in them, and you don't want that.
I hope this answer was helpful! Best of luck!
Updated on September 23rd, 2025