The state has one of the nation's lowest rates of unneeded antibiotics use.
Dr. Ann Thomas with the Oregon Health Authority says colds and the flu are usually caused by viruses and antibiotics are ineffective against them.
"So what this means for consumers is wheter you have an upper respiratory infection or a skin infection, you need to ask, do I need to be treated and if you do, is this the best drug and to talk about the side effects."
Over prescribing antibiotics can also lead to antibiotic resistance, but that remains relatively low in Oregon.
Dr. Thomas credits health care providers with working hard to reduce excessive antibiotic prescriptions.