Doxylamine, sold under the brand name Unisom among others, is an antihistamine medication which is used in the treatment of insomnia and allergies. In combination with pyridoxine (vitamin B6), it is also used to treat morning sickness in pregnant women. Doxylamine is available over-the-counter, and is used in nighttime cold medicines, such as NyQuil, as well as in pain medications containing acetaminophen and codeine, to help with sleep. The medication is taken by mouth. Side effects of doxylamine include dizziness, drowsiness, grogginess, and dry mouth, among others. Doxylamine is an antihistamine—specifically an inverse agonist of the histamine H1 receptor—and to a lesser extent an anticholinergic—specifically an antagonist of the muscarinic acetylcholine receptors M1 through M5. It is a first-generation antihistamine and crosses the blood-brain barrier into the brain, thereby producing centrally mediated sedative and hypnotic effects. Doxylamine was first described in 1948 or 1949. Several of the first-generation antihistamines, including doxylamine, are the most widely used sleep medications in the world. Medical uses
Doxylamine is an antihistamine used to treat sneezing, runny nose, watery eyes, hives, skin rash, itching, and other cold or allergy symptoms. It is also used as a short-term treatment for insomnia. Insomnia
The first-generation sedating antihistamines diphenhydramine, doxepin, doxylamine, and pyrilamine are the most widely used medications in the world for preventing and treating insomnia. As of 2004, doxylamine and diphenhydramine, which are both over-the-counter medications, were the agents most commonly used to treat short-term insomnia.
Contraindications
Hypersensitivity

Society and culture
Availability
Gatifloxacin is currently available in the US and Canada only as an ophthalmic solution.In 2011, the Union Health and Family Welfare Ministry of India banned the manufacture, sale, and distribution of gatifloxacin because of its adverse side effects.In China, gatifloxacin is sold in tablet as well as in eye drop formulations. Brand names
Bristol-Myers Squibb introduced gatifloxacin in 1999 under the proprietary name Tequin for the treatment of respiratory tract infections, having licensed the medication from Kyorin Pharmaceutical Company of Japan. Allergan produces it in eye-drop formulation under the names Zymar, Zymaxid and Zylopred. In many countries, gatifloxacin is also available as tablets and in various aqueous solutions for intravenous therapy. == References ==