; BMI , 243kg/m ( 2 ) ; fasting plasma glucose , 5.10.2 mmol/l and HbA1c , 341mmol/mol ( 5.30.1 % ) ) were randomised to two-paired study days comprising a 4-h 50g oral glucose tolerance test ( OGTT ) with paracetamol ( A ) and an isoglycaemic intravenous ( i.v. ) glucose infusion ( B ) , with ( A1 + B1 ) and without ( A2 + B2 ) preceding administration of the DPP4 inhibitor sitagliptin .