Malabsorption is a state arising from abnormality in absorption of food nutrients across the gastrointestinal (GI) tract. Impairment can be of single or multiple nutrients depending on the abnormality. This may lead to malnutrition and a variety of anaemias.Normally the human gastrointestinal tract digests and absorbs dietary nutrients with remarkable efficiency. A typical Western diet ingested by an adult in one day includes approximately 100 g of fat, 400 g of carbohydrate, 100 g of protein, 2 L of fluid, and the required sodium, potassium, chloride, calcium, vitamins, and other elements. Salivary, gastric, intestinal, hepatic, and pancreatic secretions add an additional 7–8 L of protein-, lipid-, and electrolyte-containing fluid to intestinal contents. This massive load is reduced by the small and large intestines to less than 200 g of stool that contains less than 8 g of fat, 1–2 g of nitrogen, and less than 20 mmol each of Na+, K+, Cl–, HCO3–, Ca2+, or Mg2+. If there is impairment of any of the many steps involved in the complex process of nutrient digestion and absorption, intestinal malabsorption may ensue. If the abnormality involves a single step in the absorptive process, as in primary lactase deficiency, or if the disease process is limited to the very proximal small intestine, then selective malabsorption of only a single nutrient may occur. However, generalized malabsorption of multiple dietary nutrients develops when the disease process is extensive, thus disturbing several digestive and absorptive processes, as occurs in coeliac disease with extensive involvement of the small intestine.
Angiotensin II (Ang II) is a medication that is used to treat hypotension resulting from septic shock or other distributive shock. It is a synthetic vasoconstrictor peptide that is identical to human hormone angiotensin II  and is marketed under the brand name Giapreza. The Food and Drug Administration approved the use of angiotensin II in December 2017 to treat low blood pressure resulting from septic shock.The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication. Medical uses
Angiotensin II is a vasoconstrictor used to increase blood pressure in adults with septic or other distributive shock. Angiotensin II is a naturally occurring hormone secreted as part of the renin-angiotensin system that results in powerful systemic vasoconstriction. The vasopressor effects of angiotensin have been studied since it was first isolated in the late 1930s. Vasopressors are defined as agents that combat vasodilatory shock by inducing peripheral vasoconstriction. Commonly used vasopressors include catecholamine (e.g., dopamine, norepinephrine, epinephrine) and non-catecholamine (e.g., vasopressin). but these agents are not always effective in reversing vasodilatory shock, and their use can be associated with significant side effects including limb ischemia and cardiac arrhythmia. Angiotensin II is as a treatment option that can increase blood pressure and allow catecholamine dose reductions. Angiotensin II must be administered as an intravenous infusion diluted in 0.9% sodium chloride prior to use. The recommended starting dosage of angiotensin II is 20 nanograms (ng)/kg/min via continuous intravenous infusion. Administration through a central venous line is recommended.