Obese patients with a BMI ≥ 40 kg/m2 undergoing endoscopic gastric bypass surgery will receive a 100 mg or a 200mg dose of micafungin. A PK curve will be determined after administration at t=0.5, 0.95, 1.25, 1.5, 2, 4, 8, 12, 24, and (if feasible) 48 hours post infusion. Blood samples (4 mL) on PK
All obese patients with a BMI ≥ 40 kg/m2 undergoing endoscopic gastric bypass surgery who receive a prophylactic single dose of 100 mg anidulafungin will be included in the analysis. A PK curve will be determined after administration of anidulafungin at t=0.5, 1, end of infusion, 2, 4, 6, 8, 10, 12,