Alternatively, ammonia, acetic acid and paraldehyde are used to make 5-ethyl-2-methyl-pyridine, which is then oxidized to niacin. New "greener" catalysts are being tested using manganese-substituted aluminophosphates that use acetyl peroxyborate as non-corrosive oxidant, avoiding producing nitrogen oxides as do traditional ammoxidations.The demand for commercial production includes for animal feed and for food fortification meant for human consumption. According to Ullmanns Encyclopedia of Industrial Chemistry, worldwide 31,000 tons of nicotinamide were sold in 2014. Chemistry
This colorless, water-soluble solid is a derivative of pyridine, with a carboxyl group (COOH) at the 3-position. Other forms of vitamin B3 include the corresponding amide nicotinamide (niacinamide), where the carboxyl group has been replaced by a carboxamide group (CONH2). Preparations
Niacin is incorporated into multi-vitamin and sold as a single-ingredient dietary supplement. The latter can be immediate or slow release.Nicotinamide (niacinamide) is used to treat niacin deficiency because it does not cause the flushing adverse reaction seen with niacin. Nicotinamide may be toxic to the liver at doses exceeding 3 g/day for adults.Prescription products can be immediate release (Niacor, 500 mg tablets) or extended release (Niaspan, 500 and 1000 mg tablets). Niaspan has a film coating that delays release of the niacin, resulting in an absorption over a period of 8–12 hours. This reduces vasodilation and flushing side effects, but increases the risk of hepatotoxicity compared to the immediate release drug.Prescription niacin in combination with statin drugs (discontinued) is described above. A combination of niacin and laropiprant had been approved for use in Europe and marketed as Tredaptive.
Esophageal diseases can derive from congenital conditions, or they can be acquired later in life. Many people experience a burning sensation in their chest occasionally, caused by stomach acids refluxing into the esophagus, normally called heartburn. Extended exposure to heartburn may erode the lining of the esophagus, leading potentially to Barretts esophagus which is associated with an increased risk of adenocarcinoma most commonly found in the distal one-third of the esophagus. Some people also experience a sensation known as globus esophagus, where it feels as if a ball is lodged in the lower part of the esophagus. The following are additional diseases and conditions that affect the esophagus:

Achalasia
Acute esophageal necrosis
Barretts esophagus
Boerhaave syndrome
Caustic injury to the esophagus
Chagas disease
Diffuse esophageal spasm
Esophageal atresia and tracheoesophageal fistula
Esophageal cancer
Esophageal dysphagia
Esophageal varices
Esophageal web
Esophagitis
GERD
Hiatus hernia
Jackhammer esophagus (hypercontractile peristalsis)
Killian–Jamieson diverticulum
Mallory–Weiss syndrome
Neurogenic dysphagia
Nutcracker esophagus
Schatzkis ring
Zenkers diverticulum

References
External links

Esophageal and Swallowing Disorders, Merck & Company Inc.