3 yr old lab/chow RED ear

My dog's ear is bright RED, there are no black/brown stuff in it.  He shakes his head when I try to touch it.  Is there anything I can sure over the counter to help him?  Can I give him anything for the discomfort? I clean his ears once a week or as needed.  He started this about 2 days ago when he got into a river after it rained.  I never let him swim in the river.  So I need help on what to do.  Thanks

[Aleda M Cheng, D.V.M., C.V.A]

Of course you should take him to the veterinarian for proper diagnosis and ear cytology.

In the mean time you can try an OTC preperation for human swimmer's ear, and a topical monostat or other cream for yeast.  Place a small amount of the monostat cream in the affected ear after placing in the swimmer's ear lotion.  If there is no improvement in 2 days you really must go to a veterinarian to avoid an aural hematoma, and permanently disfiguring your dogs ear, not to mention the pain he could be suffering.