poison oak on my 10 year old chihuahua

Question
hello,
I live in the center coast of california and I think my dog has
come into contact with some kind of poison oak or poison plant.  On tuesday(3 days ago) I noticed he had these red bumps on his body that where uncomfortable for him.  At first I thought he had a skin rash from the oatmeal shampoo(he got a bath the day before)which happened once when he was a young pup.  At that time my vet told me what to do if it happened again.  I did I gave him baby advil or children's allergy med.  It's helped but he still very uncomfortable and not happy.  I then remembered we have some kind of poison plant in the back yard.  I have also started to apply some calamine lotion to his skin where it is red and irrirated.  I am not able to go to his vet until at least next thursday.  what can I do to help treat him.  Is it poison oak?  Thank you for your help.

Answer
Dogs rarely get the effect of poison ivy or poison oak.  The treatment for that type of skin problem is high doses of steroids. Red bumps usually indicated a skin infection called folliculitis.  That may be a Staph infection and it will most likely respond to antibiotics, like cephalexin.