One symptom of gas that is not normally associated with it is the hiccup. Hiccups are harmless and will diminish on their own; they also help to release gas that is in the digestive tract before it moves down to the intestines and causes bloating. Important but uncommon causes of abdominal bloating include ascites and tumors. Causes
There are many causes of bloating, including: diet, irritable bowel syndrome, lactose intolerance, reflux, and constipation. Specific medical conditions like Crohns disease or bowel obstruction can also contribute to the amount of stomach bloating experienced. Common causes of abdominal bloating are:

Overeating
Gastric distension
Lactose intolerance, fructose intolerance and other food intolerances
Premenstrual syndrome
Food allergy
Aerophagia (air swallowing, a nervous habit)
Irritable bowel syndrome
Celiac disease
Non-celiac gluten sensitivity
Partial bowel obstruction
Gastric dumping syndrome or rapid gastric emptying
Gas-producing foods
Constipation
Visceral fat
Splenic-flexure syndrome
Menstruation, dysmenorrhea
Polycystic ovary syndrome and ovarian cysts
Alvarez syndrome, bloating of unknown or psychogenic origin without excess gas in the digestive tract
Massive infestation with intestinal parasites (e.g., Ascaris lumbricoides)
Diverticulosis
Certain medications, such as phentermine
Occurs in some due to salivary hypersecretion and dehydration.
Medications
There are many over-the-counter (OTC) medications that can be used to treat bloating. Food enzymes can be found in some products that will help break down the sugars found in grains, vegetables and dairy products. They can be taken before food is consumed or added to the food that causes the gas and bloating. The most common treatment is antacids. These medications have no effect on the gas that is present in the intestines but enable gas build-up to be belched away more easily, reducing the amount of bloating that develops. Another treatment is simethicone, an oral anti-foaming agent that helps the body to expel the gas more quickly. Combinations of prokinetics, such as domperidone + metoclopramide + diphenhydramine (the latter for the prevention of extrapyramidal reactions, especially acute dystonic reactions) + proton pump inhibitors (PPIs), have dramatic effects on bloaters and belchers especially. See also
Tympany

References
Notes

Bibliography

Partly based on Abdominal bloating. MedlinePlus (US public domain Medical Encyclopedia). Update Date: 10 November 2004. Updated by: Christian Stone, M.D., Division of Gastroenterology, Washington University in St. Louis School of Medicine, St. Louis, MO. Review provided by VeriMed Healthcare Network. Ahmed Shazly. Van Vorous, Heather. Eating for IBS. 2000. ISBN 1-56924-600-9. Excerpted with authors permission at Help for Irritable Bowel Syndrome (see IBS Diet Section)
(2021, January 16) Lower back pain and bloated tummy: causes and best treatments - Everything to Know about Back Muscles.