Diabetes insipidus (DI) is a condition characterized by large amounts of dilute urine and increased thirst. The amount of urine produced can be nearly 20 liters per day. Reduction of fluid has little effect on the concentration of the urine. Complications may include dehydration or seizures.
Hyponatremia or hyponatraemia is a low concentration of sodium in the blood. It is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe hyponatremia being below 120 mEq/L. Symptoms can be absent, mild or severe. Mild symptoms include a decreased ability to think, headaches, nausea, and poor balance. Severe symptoms include confusion, seizures, and coma; death can ensue.
Human vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP) or argipressin, is a hormone synthesized from the AVP gene as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then travels down the axon terminating in the posterior pituitary, and is released from vesicles into the circulation in response to extracellular fluid hypertonicity (hyperosmolality). AVP has two primary functions. First, it increases the amount of solute-free water reabsorbed back into the circulation from the filtrate in the kidney tubules of the nephrons. Second, AVP constricts arterioles, which increases peripheral vascular resistance and raises arterial blood pressure.
Alcoholic liver disease (ALD), also called alcohol-related liver disease (ARLD), is a term that encompasses the liver manifestations of alcohol overconsumption, including fatty liver, alcoholic hepatitis, and chronic hepatitis with liver fibrosis or cirrhosis.
Von Willebrand disease (VWD) is the most common hereditary blood-clotting disorder in humans. An acquired form can sometimes result from other medical conditions. It arises from a deficiency in the quality or quantity of von Willebrand factor (VWF), a multimeric protein that is required for platelet adhesion. It is known to affect several breeds of dogs as well as humans. The three forms of VWD are hereditary, acquired, and pseudo or platelet type. The three types of hereditary VWD are VWD type 1, VWD type 2, and VWD type 3. Type 2 contains various subtypes. Platelet type VWD is also an inherited condition.
Hypopituitarism is the decreased (hypo) secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain. If there is decreased secretion of one specific pituitary hormone, the condition is known as selective hypopituitarism. If there is decreased secretion of most or all pituitary hormones, the term panhypopituitarism is used.
Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue.
Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by excessive unsuppressible release of antidiuretic hormone (ADH) either from the posterior pituitary gland, or an abnormal non-pituitary source. Unsuppressed ADH causes an unrelenting increase in solute-free water being returned by the tubules of the kidney to the venous circulation.
Hepatorenal syndrome is a life-threatening medical condition that consists of rapid deterioration in kidney function in individuals with cirrhosis or fulminant liver failure. HRS is usually fatal unless a liver transplant is performed, although various treatments, such as dialysis, can prevent advancement of the condition.
Nocturia is defined by the International Continence Society (ICS) as “the complaint that the individual has to wake at night one or more times for voiding .” The term is derived from Latin nox, night, and Greek [τα] ούρα, urine. Causes are varied and can be difficult to discern. Although not every patient needs treatment, most people seek treatment for severe nocturia, waking up to void more than 2–3 times per night.
Primary polydipsia and psychogenic polydipsia are forms of polydipsia characterised by excessive fluid intake in the absence of physiological stimuli to drink. Psychogenic polydipsia which is caused by psychiatric disorders, often schizophrenia, is often accompanied by the sensation of dry mouth. Some forms of polydipsia are explicitly non-psychogenic. Primary polydipsia is a diagnosis of exclusion.
Vasopressin V1b receptor (V1BR) also known as vasopressin 3 receptor (VPR3) or antidiuretic hormone receptor 1B is a protein that in humans is encoded by the AVPR1B gene.
Vasopressin receptor 2 (V2R), or arginine vasopressin receptor 2, is a protein that acts as receptor for vasopressin. AVPR2 belongs to the subfamily of G-protein-coupled receptors. Its activity is mediated by the Gs type of G proteins, which stimulate adenylate cyclase.
An antidiuretic is a substance that helps to control fluid balance in an animal's body by reducing urination, opposing diuresis. Its effects are opposite that of a diuretic. The major endogenous antidiuretics are antidiuretic hormone and oxytocin. Both of those are also used exogenously as medications in people whose bodies need extra help with fluid balance via suppression of diuresis. In addition, there are various other antidiuretic drugs, some molecularly close to ADH or oxytocin and others not. Antidiuretics reduce urine volume, particularly in diabetes insipidus (DI), which is one of their main indications.
A vasopressin receptor antagonist (VRA) is an agent that interferes with action at the vasopressin receptors. Most commonly VRAs are used in the treatment of hyponatremia, especially in patients with congestive heart failure, liver cirrhosis or SIADH.
Central diabetes insipidus, also called neurogenic diabetes insipidus, is a type of diabetes insipidus due to a lack of vasopressin (ADH) production in the brain. Vasopressin acts to increase the volume of blood (intravascularly), and decrease the volume of urine produced. Therefore, a lack of it causes increased urine production and volume depletion.
Hypoosmolar hyponatremia is a condition where hyponatremia associated with a low plasma osmolality. The term "hypotonic hyponatremia" is also sometimes used.
Adipsia, also known as hypodipsia, is a symptom of inappropriately decreased or absent feelings of thirst. It involves an increased osmolality or concentration of solute in the urine, which stimulates secretion of antidiuretic hormone (ADH) from the hypothalamus to the kidneys. This causes the person to retain water and ultimately become unable to feel thirst. Due to its rarity, the disorder has not been the subject of many research studies.
Vasopressin infusions are in use for septic shock patients not responding to fluid resuscitation or infusions of catecholamines to increase the blood pressure while sparing the use of catecholamines. These argipressins have much shorter elimination half-life than synthetic non-arginine vasopresines with much longer elimination half-life of many hours. Further, argipressins act on V1a, V1b, and V2 receptors which consequently lead to higher eGFR and lower vascular resistance in the lungs. A number of injectable arginine vasopressins are in clinical use in the United States and the European Union. Pitressin among others, is a medication most commonly used in the treatment of frequent urination, increased thirst, and dehydration such as that resulting from diabetes insipidus, which causes increased and diluted urine. It is used to treat abdominal distension following some surgeries, and in stomach roentgenography. Vasopressin is a hormone that affects the kidneys and reduces urine flow.
Sofosbuvir/velpatasvir, sold under the brand name Epclusa among others, is a fixed-dose combination medication for the treatment of hepatitis C in adults. It combines sofosbuvir and velpatasvir. It is more than 90% effective for hepatitis C genotypes one through six. It also works for hepatitis C in those who also have cirrhosis or HIV/AIDS. It is taken by mouth.
