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Ephedrine hydrochloride

Ephedrine is a medication and stimulant. It is often used to prevent low blood pressure during spinal anesthesia. It has also been used for asthma, narcolepsy, and obesity but is not the preferred treatment. It is of unclear benefit in nasal congestion. It can be taken by mouth or by injection into a muscle, vein, or just under the skin. Onset with intravenous use is fast, while injection into a muscle can take 20 minutes, and by mouth can take an hour for effect. When given by injection it lasts about an hour and when taken by mouth it can last up to four hours. Ephedrine is a medication and stimulant. It is often used to prevent low blood pressure during spinal anesthesia. It has also been used for asthma, narcolepsy, and obesity but is not the preferred treatment. It is of unclear benefit in nasal congestion. It can be taken by mouth or by injection into a muscle, vein, or just under the skin. Onset with intravenous use is fast, while injection into a muscle can take 20 minutes, and by mouth can take an hour for effect. When given by injection it lasts about an hour and when taken by mouth it can last up to four hours. Common side effects include trouble sleeping, anxiety, headache, hallucinations, high blood pressure, fast heart rate, loss of appetite, and inability to urinate. Serious side effects include stroke, heart attack, and abuse. While likely safe in pregnancy, its use in this population is poorly studied. Use during breastfeeding is not recommended. Ephedrine works by increasing the activity of the α and β adrenergic receptors. Ephedrine was first isolated in 1885 and came into commercial use in 1926. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. It is available as a generic medication. The wholesale cost in the developing world is about US$0.69–1.35 per dose. In the United States it is not very expensive. It can normally be found in plants of the Ephedra type. Dietary supplements containing ephedrine are illegal in the United States, with the exception of those used in traditional Chinese medicine, where its presence is noted by má huáng. Both ephedrine and pseudoephedrine increase blood pressure and act as bronchodilators, with pseudoephedrine having considerably less effect. Ephedrine may decrease motion sickness, but it has mainly been used to decrease the sedating effects of other medications used for motion sickness. Ephedrine promotes modest short-term weight loss, specifically fat loss, but its long-term effects are unknown. In mice, ephedrine is known to stimulate thermogenesis in the brown adipose tissue, but because adult humans have only small amounts of brown fat, thermogenesis is assumed to take place mostly in the skeletal muscle. Ephedrine also decreases gastric emptying. Methylxanthines such as caffeine and theophylline have a synergistic effect with ephedrine with respect to weight loss. This led to creation and marketing of compound products. One of them, known as the ECA stack, contains ephedrine with caffeine and aspirin. It is a popular supplement taken by bodybuilders seeking to cut body fat before a competition. As a phenethylamine, ephedrine has a similar chemical structure to amphetamines and is a methamphetamine analogue having the methamphetamine structure with a hydroxyl group at the β position. Because of ephedrine's structural similarity to methamphetamine, it can be used to create methamphetamine using chemical reduction in which ephedrine's hydroxyl group is removed; this has made ephedrine a highly sought-after chemical precursor in the illicit manufacture of methamphetamine. The most popular method for reducing ephedrine to methamphetamine is similar to the Birch reduction, in that it uses anhydrous ammonia and lithium metal in the reaction. The second-most popular method uses red phosphorus and iodine in the reaction with ephedrine. Moreover, ephedrine can be synthesized into methcathinone via simple oxidation. As such, ephedrine is listed as a table-I precursor under the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances. Ephedrine may be quantified in blood, plasma, or urine to monitor possible abuse by athletes, confirm a diagnosis of poisoning, or assist in a medicolegal death investigation. Many commercial immunoassay screening tests directed at the amphetamines cross-react appreciably with ephedrine, but chromatographic techniques can easily distinguish ephedrine from other phenethylamine derivatives. Blood or plasma ephedrine concentrations are typically in the 20-200 µg/l range in persons taking the drug therapeutically, 300-3000 µg/l in abusers or poisoned patients and 3–20 mg/l in cases of acute fatal overdosage. The current WADA limit for ephedrine in an athlete's urine is 10 µg/ml. Ephedrine should not be used in conjunction with certain antidepressants, namely norepinephrine-dopamine reuptake inhibitors (NDRIs), as this increases the risk of symptoms due to excessive serum levels of norepinephrine.

[ "High-performance liquid chromatography", "Ephedrine", "Wavelength" ]
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