what diuretics cause low white blood cell count? age 64, female, height 5 feet 9 inches, weight 152 pounds. Taking 1/2 of a 37.5 mg tablet of HCTZ daily for a mild diuretic. White blood cell count is 3 to 3.8, variable. Been that way for 3 or 4 years. The rest of the hemogram is normal. Negative medical history otherwise, except for hypothyroidism. Exercise regularly. Eating healthy diet, low in fat, lots of veggies and fruit.