Methylene Blue trihydrate 25g powder
Methylene Blue trihydrate 25g powder
Methylthioninium chloride, commonly called methylene blue, is a salt used as a dye and as a medication. Methylene blue is a thiazine dye. It works by converting the ferric iron in hemoglobin to ferrous iron. As a medication, it is mainly used to treat methemoglobinemia. Specifically, it is used to treat methemoglobin levels that are greater than 30% or in which there are symptoms despite oxygen therapy. It has previously been used for cyanide poisoning and urinary tract infections, but this use is no longer recommended.
Methylene blue is typically given by injection into a vein. Common side effects include headache, vomiting, confusion, shortness of breath, and high blood pressure. Other side effects include serotonin syndrome, red blood cell breakdown, and allergic reactions. Use often turns the urine, sweat, and stool blue to green in color. While use during pregnancy may harm the baby, not using it in methemoglobinemia is likely more dangerous.
Methylene blue was first prepared in 1876, by Heinrich Caro. It is on the World Health Organization’s List of Essential Medicines.
History
Methylene blue has been described as “the first fully synthetic drug used in medicine.” Methylene blue was first prepared in 1876 by German chemist Heinrich Caro.
Its use in the treatment of malaria was pioneered by Paul Guttmann and Paul Ehrlich in 1891. During this period before the first World War, researchers like Ehrlich believed that drugs and dyes worked in the same way, by preferentially staining pathogens and possibly harming them. Changing the cell membrane of pathogens is in fact how various drugs work, so the theory was partially correct although far from complete. Methylene blue continued to be used in the second World War, where it was not well liked by soldiers, who observed, “Even at the loo, we see, we pee, navy blue.” Antimalarial use of the drug has recently been revived. It was discovered to be an antidote to carbon monoxide poisoning and cyanide poisoning in 1933 by Matilda Brooks.
The blue urine was used to monitor psychiatric patients’ compliance with medication regimes. This led to interest – from the 1890s to the present day – in the drug’s antidepressant and other psychotropic effects. It became the lead compound in research leading to the discovery of chlorpromazine.
Names
The International Nonproprietary Name (INN) of methylene blue is methylthioninium chloride.