Scleroderma is a disease characterized by atrophy and sclerosis of the gut wall, most commonly of the distal esophagus (~90%). Consequently, the lower esophageal sphincter cannot close and this can lead to severe gastroesophageal reflux disease (GERD). Patients typically present with progressive dysphagia to both solids and liquids secondary to motility problems or peptic stricture from acid reflux. Spastic motility disorders include diffuse esophageal spasm (DES), nutcracker esophagus, hypertensive lower esophageal sphincter, and nonspecific spastic esophageal motility disorders (NEMD). DES can be caused by many factors that affect muscular or neural functions, including acid reflux, stress, hot or cold food, or carbonated drinks. Patients present with intermittent dysphagia, chest pain, or heartburn.Rare causes of esophageal dysphagia not mentioned above

Diverticulum
Aberrant subclavian artery, or (dysphagia lusoria)
Cervical osteophytes
Enlarged aorta
Enlarged left atrium
Mediastinal tumor

Diagnostic tools
Once a patient complains of dysphagia they should have an upper endoscopy (EGD). Commonly patients are found to have esophagitis and may have an esophageal stricture. Biopsies are usually done to look for evidence of esophagitis even if the EGD is normal. Usually no further testing is required if the diagnosis is established on EGD. Repeat endoscopy may be needed for follow up. If there is a suspicion of a proximal lesion such as:

history of surgery for laryngeal or esophageal cancer
history of radiation or irritating injury
achalasia
Zenkers diverticuluma barium swallow may be performed before endoscopy to help identify abnormalities that might increase the risk of perforation at the time of endoscopy.
The company had a group of enthusiastic self-experimenters that called itself the "Death Battalion", and in the course of testing the drug on themselves, accidentally discovered that drinking alcohol while the drug was still in their bodies  made them mildly sick. : 98–105 They made that discovery in 1945, and did nothing with it until two years later, when Jacobsen gave an impromptu talk and mentioned that work, which was discussed afterwards in newspapers at the time, leading them to further explore the use of the drug for that purpose. : 98–105  That work included small clinical trials with Oluf Martensen-Larsen, a doctor who worked with alcoholics. They published their work starting in 1948.The chemists at Medicinalco discovered a new form of disulfiram while trying to purify a batch that had been contaminated with copper. This form turned out to have better pharmacological properties, and the company patented it and used that form for the product that was introduced as Antabus (later anglicized to Antabuse).This work led to renewed study of the human metabolism of ethanol. It was already known that ethanol was mostly metabolized in the liver, with it being converted first to acetaldehyde and then acetaldehyde to acetic acid and carbon dioxide, but the enzymes involved were not known.