Hyponatremia Hyponatremia Hyponatremia is a low sodium level 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. The causes of hyponatremia are typically classified by a person's body fluid status into low volume, normal volume, or high volume. Low volume hyponatremia can occur from diarrhea, vomiting, diuretics, and sweating. Normal volume hyponatremia is divided into cases with dilute
Serum sickness Serum sickness Serum sickness in humans is a reaction to proteins in antiserum derived from a non-human animal source, occurring 5–10 days after exposure. It is a type of hypersensitivity, specifically immune complex hypersensitivity (type III). The term serum sickness–like reaction (SSLR) is occasionally used to refer to similar illnesses that arise from the introduction of certain non-protein substances, such as penicillin. It was first characterized by Clemens von Pirquet and Béla Schick in 1906. When an antiserum is given, the human immune system can mistake the proteins present for harmful antigens. The body produces antibodies, which combine with these