Hi thanks for your question.
Gastric or duodenal ulcers are caused by increased acid output in stomach. There are many causes of increased acid output. The common ones are infection of the stomach by H Pylori bacteria, spicy food,
cigarette smoking, alcohol, pain killer drugs and yes of course
stress. Ulcers usually take 8 to 1o weeks time to heal after treatment for eradication of H Pylori bacteria. However some time the H Pylori is resistant to treatment and symptoms persists in spite of treatment. In such cases a check
endoscopy or C14 urea test is done to check for eradication of
H Pylori infection. In case the infection is persistent a second course of second line drugs are given to eradicate the infection. Yes drinking beer can make the symptoms worst. Ulcer is caused when the protective layer of stomach is destroyed by increased acid .Yes ulcer causes
sharp pain in abdomen and it also causes swelling of stomach. The antibiotic used for treatment of ulcer kill the bacteria and
proton pump used for healing the ulcer block the acid production, by which gastric Ph is raised and ulcer get healed.H Pylori bacteria is normal flora of stomach.
Hope this answers your question