Alcohol and Gastrointestinal Tract

Mouth

Chronic drinking increases the risk of tooth decay and teeth loss, inflammation of the tongue (glossitis), black hairy tongue, inflammation of the gums (gingivitis) and oral cancer ^[1,49].

Alcohol and Dry Mouth

Alcohol-related causes of dry mouth:

• Alcohol, which has a direct drying effect on the mouth lining
• Dehydration and anxiety during hangover or alcohol withdrawal ^[2,3]
• Advanced alcoholic liver disease (hepatitis, cirrhosis) ^[4]
• Parotid glands enlargement (sialosis or sialadenosis) ^[5]

Alcohol, Bad Breath (Halitosis) and Body Odor

People may have a distinct alcohol-smelling breath after a single drink. There is poor correlation between the amount or strength of alcohol drunk and the strength of breath odor. Pure alcohol has little smell, so drinking vodka may result in less breath odor than drinking beer ^[6].

In chronic drinkers who drink but eat only a little, excessive breakdown of the body fat can result in a buildup of ketones in the blood (ketosis or ketoacidosis). One of the ketones, called acetone, gives a sweet, fruity odor to the breath ^[7]. Acetone breath also occurs in those who are fasting or starving, are on a low-carbohydrate (Atkins) diet or have poorly controlled diabetes type 1 or 2.

Other possible causes of bad breath in chronic alcoholics include lack of mouth hygiene, tooth decay, gum disease, smoking, sialosis (parotid gland enlargement) ^[5], chronic bronchitis, lung infection, acid reflux, gastritis (inflammation of the stomach), liver disease ^[8] and mouth, throat, esophageal or gastric cancer.

Chronic alcoholics may have persistent reek, an offensive odor in their breath, skin, clothes and rooms where they live. The odor is worse after drinking and may go away only after few weeks of abstinence.

Salivary Glands

Sialosis or sialadenosis refers to enlarged, swollen, soft, painless parotid glands on both sides bellow the ears often seen in chronic drinkers with nutrient deficiencies, advanced alcoholic hepatitis or cirrhosis ^[9]. Rarely, the salivary glands bellow the tongue and jaw are enlarged ^[10].

Throat

Heavy binge or chronic drinking may cause the inflammation of the voice box (laryngitis) with swelling, dryness, nodules or polyps in the vocal cords and hoarseness ^[11]. Acid reflux, common in alcoholics, may also cause hoarseness ^[12].

Chronic alcohol consumption increase the risk of pharyngeal and laryngeal (voice box) cancer ^[49].

Esophagus

Gastro-Esophageal Reflux Disease (GERD)

Ethanol can relax the muscle on the bottom of the esophagus called the lower esophageal sphincter (LES), which may result in the back-flow of the stomach acid into esophagus (gastric reflux) ^[12]. with heartburn. Complications may include an inflammation of the esophagus (esophagitis) with the pain behind the breastbone and painful swallowing, precancerous lesions (Barrett’s esophagus) or esophageal cancer ^[49].

Esophageal spasms may be related to alcohol-induced gastric reflux or damage of the esophageal nerves. The main symptom is severe crampy pain during eating that may mimic heart attack ^[50].

In chronic alcoholics with liver cirrhosis, the increased pressure in the esophageal veins may cause esophageal varices with difficulty swallowing and, when they rupture, chest pain, vomiting blood and black stools; the bleeding may be fatal ^[13,51].

Repeated retching and vomiting may result in a rupture of the esophageal mucosal lining at the bottom of the esophagus (Mallory-Weiss Syndrome) ^[14]. Symptoms include chest pain, vomiting bright red blood and blood in the stool after intense vomiting ^[14]. Spontaneous healing is common and the prognosis is good; rarely, surgery is required ^[14].

Stomach

Heavy drinking may cause inflammation of the stomach (acute gastritis) with gnawing upper abdominal pain that may radiate to the back, abdominal discomfort and early satiety ^[15,16]. Symptoms usually go away without treatment within a week of alcohol abstinence ^[16].

Chronic atrophic gastritis with abdominal bloating, nausea or frequent burping is common in chronic alcoholics; the cause is the infection with the bacterium Helycobacter pylori ^[17,18]. Treatment is by antibiotics ^[17].

Fermented alcoholic beverages, such as beer, wine, sherry and martini (probably due to succinic and maleic acid content), increase gastric acid secretion, while spirits, such as whiskey, cognac, rum, calvados and campari, do not have any significant effect on the acid secretion ^{[19,20,21,22,23,24,25]}. Alcoholics may have increased, decreases or normal gastric secretion ^[20,23]. Alcohol itself probably does not cause stomach or duodenal ulcer, but can aggravate the established ulcer ^[18,26]. Individuals who smoke and drink alcohol are at increased risk of developing peptic ulcer ^[27].

Small Intestine

In one study, the mean small bowel transit time in healthy abstainers and moderate drinkers was about 1.5 hours and in chronic alcoholics about 3 hours ^[35]. The prolonged bowel transit time may contribute to small intestinal bacterial overgrowth (SIBO) with abdominal bloating, flatulence, diarrhea or constipation ^[37].

Alcohol and Leaky Gut

Alcohol promotes bacterial growth in the intestine and increases the gut permeability, thus allowing bacterial toxins to enter the circulation and damage the liver ^[28]. This is one possible mechanism of alcohol liver disease. The growth of harmful bacteria and and thus the risk of alcoholic liver disease may be reduced by probiotics (Bifidobacteria, Lactobacillus GG), zinc supplements, oat bran, L-glutamine and epidermal growth factor (EGF) ^[28].

Colon and Rectum

• In chronic alcoholics with liver cirrhosis, hemorrhoids may develop due to increased pressure in the rectal veins ^[48].
• Alcohol consumption may worsen symptoms of inflammatory bowel disease (Crohn’s disease, ulcerative colitis) ^[29,30].
• Heavy beer drinking may increase the risk of colorectal cancer, and moderate wine drinking may decrease it ^[31,32]. According to one 2011 study, alcohol consumption of more than one drink per day may increase the risk of colorectal cancer ^[32,33,49].
• According to one large 1995 study there is no association between alcohol intake and diverticular disease ^[34].

Pancreas

Acute Pancreatitis

Acute pancreatitis usually develops in a person with chronic pancreatitis. Symptoms include severe upper middle abdominal pain that radiates to the back and lasts for more than a day, nausea, vomiting and, sometimes, fever ^[36]. Treatment requires hospitalization; full recovery without consequences is common, but severe acute pancreatitis may be deadly, despite treatment ^[38,39,40].

Chronic Pancreatitis

Chronic pancreatitis is an inflammation of the pancreas, which more likely affects those who drink at least 7 drinks per day for at least 5 years and have a genetic predisposition for it ^[41]. Only about 10% of heavy drinkers develop chronic pancreatitis ^[42]. It is not clear if the type of alcoholic beverage (beer, wine, spirits) or pattern of drinking affects the risk of developing chronic pancreatitis. Symptoms include chronic or recurring pain in the upper middle abdomen, which may radiate to the back; pain may be aggravated by alcohol or meals and may last for several hours ^[43,44]. Severe chronic pancreatitis may contribute to development of diabetes type 2, fat malabsorption and chronic diarrhea ^[45].

Treatment includes alcohol abstinence, painkillers, pancreatic enzymes, vitamins or surgery ^[46,47]. Prognosis depends on continuing drinking and other conditions, such as liver cirrhosis; 10-years survival rate is about 70% ^[45]. Chronic pancreatitis is irreversible, so it cannot be cured completely, but symptoms may improve after stopping drinking ^[45,47].