Old Medical Advice: If your mucus is green, you have a bacterial infection and need an antibiotic. Many doctors still believe this myth because it seems biologically plausible, says Rachel Vreeman, MD, assistant professor of pediatrics at Indiana University and coauthor of Don’t Cross Your Eyes … They’ll Get Stuck That Way. A yellow or greenish-looking nasal discharge suggests that bacteria are present and producing pus. But the science has shown this isn’t always true.
New Medical Advice: Don’t press your doctor for antibiotics. The tinted mucus is a normal by-product of the healing process. To fight an infection, white blood cells release enzymes to kill invaders. Some enzymes contain iron, which has a greenish color. Cloudy mucus doesn’t automatically signify a bacterial infection. “You’re likely battling a virus, which will go away on its own,” says Aaron Carroll, MD, Dr. Vreeman’s coauthor.
So why does your doc still break out the prescription pad? Some physicians just assume patients want an antibiotic because they often request one. But overprescribing has consequences. “Giving people more antibiotics can lead to resistance,” says Dr. Carroll. If your doctor suggests an antibiotic, ask if it’s really necessary.
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