This increases the acid strength of the boric acid, permitting better precision in volumetric analysis of this acid. Other
Mannitol is the primary ingredient of mannitol salt agar, a bacterial growth medium, and is used in others. Mannitol is used as a cutting agent in various drugs that are used intranasally (snorted), such as cocaine. A mixture of mannitol and fentanyl (or fentanyl analogs) in ratio 1:10 is labeled and sold as "China white", a popular heroin substitute. Contraindications
Mannitol is contraindicated in people with anuria, severe hypovolemia, pre-existing severe pulmonary vascular congestion or pulmonary edema, irritable bowel syndrome (IBS), and active intracranial bleeding except during craniotomy.Adverse effects include hyponatremia and volume depletion leading to metabolic acidosis. Chemistry
Mannitol is an isomer of sorbitol, another sugar alcohol; the two differ only in the orientation of the hydroxyl group on carbon 2. While similar, the two sugar alcohols have very different sources in nature, melting points, and uses. Production
Mannitol is classified as a sugar alcohol; that is, it can be derived from a sugar (mannose) by reduction. Other sugar alcohols include xylitol and sorbitol. Mannitol and sorbitol are isomers, the only difference being the orientation of the hydroxyl group on carbon 2. Industrial synthesis
Mannitol is commonly produced via the hydrogenation of fructose, which is formed from either starch or sucrose (common table sugar). Although starch is a cheaper source than sucrose, the transformation of starch is much more complicated. Eventually, it yields a syrup containing about 42% fructose, 52% glucose, and 6% maltose.
Ethinylestradiol/levonorgestrel (EE/LNG) is a combined birth control pill made up of ethinylestradiol, an estrogen and  levonorgestrel a progestin. It is used for birth control, symptoms of menstruation, endometriosis, and as emergency contraception. It is taken by mouth. Some preparations of EE/LNG additionally contain an iron supplement in the form of ferrous bisglycinate or ferrous fumarate.Side effects can include nausea, headache, blood clots, breast pain, depression, and liver problems. Use is not recommended during pregnancy, the initial three weeks after childbirth, and in those at high risk of blood clots. However, it may be started immediately after a miscarriage or abortion. Smoking while using combined birth control pills is not recommended. It works by stopping ovulation, making the mucus at the opening to the cervix thick, and making the uterus not suitable for implantation.Ethinylestradiol/levonorgestrel has been approved for medical use in the United States at least since 1982. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication. It is marketed under a large number of brand names. In 2019, it was the 124th most commonly prescribed medication in the United States, with more than 5 million prescriptions. See also
Birth control pill formulations
List of combined sex-hormonal preparations


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