My 11 yr.old German Shepherd has a runny nose mostly clear. Sometimes it is yellow. When he sneezes it sounds like he has nasal congestion. Does not like his nose touched. He does have allergies and colitis. He is on Hill's Presc. R/D for his colitis and is also on Rimadyl for hip problems. He also is on Soloxine .8mg a day for thyroid. He weighs 100 lbs. Is this runny nose due to an infection or allergies? Sometimes when he is sleeping he makes a clicking sound in his nose like congested. He has an appetite.
If the discharge is yellow then it is probably an infection. I recommend a visit to the vet. Good luck, vetcare