Hello, The treatment of the green phlegm depends upon the clinical diagnosis which may be pneumonia, bronchitis, sinusitis, cystic fibrosis, and others. Diagnosis has to be evaluated by expert physician, till you get that I suggest as: • Gargles with salted lukewarm water and added peppermint oil 3 times/day • Inhalation of vapors of boiling water with added tincture benzoin and blanket over the head 12 hourly • Plenty of liquids orally with soft light diet • Avoid exposure to excess cold • Keep record of body temperature • Systemic antibiotics with decongestants and expectorants are to be decided by the examiner only • Turmeric powder in boiled milk, honey, and basil leaves are natural herbs to be supportive to some extent Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Bhagyesh V. Patel