AbstractCystic fibrosis (CF) is an autosomal recessive genetic disorder. We report a case of a boy aged 4.5 years with cystic fibrosis, presenting under‐weightness, hypocalcemia, metabolic alkalosis, hypokalemia, and hyponatremia. Sweat analysis of the patients concluded pseudo‐Bartter syndrome, which was successfully treated using antibiotics, physiotherapy, fluids, vitamin supplements, and pancreatic enzyme therapy.