How would one code an under-dosing of Losartan? It is not in the ICD-10 book Drug list under Lorsartan or Cozaar. It is an angiotensin receptor blocker,and that is also not on the drub list. T44.5X6A give us angiotesin in the box above the code, but this is for beta-adrenoreceptor agonist. Any ideas.