Nausea and Vomiting
Nausea and vomiting can occur in association with infectious and noninfectious GI disorders, pregnancy and motion sickness. They can also follow the administration of many drugs including cancer chemotherapy, antibiotics, narcotic pain medications and nonsteroidal anti-inflammatory drugs such as ibuprofen. There is a vomiting center in the brain that receives signals from multiple sites and once stimulated causes the natural motility of the stomach to be reduced so that gastric reflux occurs. Vomiting results when the stomach relaxes, the passage from the stomach to the intestine constricts and the contractions of surrounding muscles cause expulsion of the gastric contents.
Several chemicals in the body are involved in the transmission of information passing into and out of the vomiting center. Drugs used to block these chemicals are used to treat nausea and vomiting. The chemicals being blocked are involved in many other bodily functions, so many drugs used to treat nausea and vomiting have other uses. For example, drugs categorized as major tranquilizers, antihistamines, antianxiety agents, and corticosteroids are often effective. Transderm Scop® (Novartis Pharmaceuticals) contains an antihistamine substance in a patch formulation. It is used to prevent motion sickness and is applied to the skin at least 4 hours before travel. Tetrahydrocannabinol (from Cannabissativa) is sometimes used for the relief of nausea and vomiting from cancer chemotherapy. Due to the ability of causing physical and psychological dependence and hallucinations, it is reserved for patients who have not responded to other forms of treatment.
Bismuth subsalicylate preparations including Pepto Bismol® are available OTC and are helpful in some cases of nausea and vomiting due to their local antiinfective actions, direct mucosal protective effects, and weak antacid properties.
Herbal supplements or teas containing ginger are often used to decrease nausea and vomiting. The mechanism by which it acts is unclear. Ginger increases saliva formation and stimulates movements in the intestine but it does not seem to effect stomach emptying. A component of ginger, galanolactone, blocks one of the chemicals involved in stimulating vomiting. As with other herbal supplements, there is currently no standardized measure to compare the potency or ingredient content of products that contain ginger so the effectiveness of preparations can vary widely. Another natural product sometimes used to decrease nausea and vomiting, particularly when associated with pregnancy, is vitamin B6 (pyridoxine).
Diarrhea has many causes. It is associated with diseases of inflammation (Crohn’s), bacteria, viruses, fungi, and parasites. It can also be caused by food poisoning, chemical poisons, and drugs – such as magnesium-containing antacids and some antibiotics. Acute diarrhea is usually self-limiting and resolves within 24 hours. Prolonged episodes of diarrhea can cause dehydration and electrolyte disorders and require medical attention. Some forms of diarrhea are treated by the use of prescription drugs that slow GI motility (Lomotil®, Imodium®) but these drugs are generally not used in cases of poisoning, diarrhea caused by toxin-producing bacteria and with an infectious condition called pseudomembranous colitis.
Several over-the-counter (OTC) drugs for uncomplicated diarrhea are available. Pepto-Bismol® (bismuth subsalicylate) has antiinfective actions, a protective effect on the gastric lining, and weak antacid activity. It is sometimes used to prevent traveler’s diarrhea. Kaopectate® (attapulgite) is thought to act by absorbing bacteria and toxins, and reducing water loss. Lactobacillus containing preparations may be used to prevent and treat uncomplicated diarrhea associated with antibiotic use. These products act to maintain the normal bacterial content of the intestinal tract.
Constipation is an infrequent passage of usually dry, hardened stools. It has a number of causes including infection, neurological disorder, and many different disease states. Dehydration and lack of exercise are contributing factors. Medications can also cause constipation, including narcotics, antihistamines, some antidepressants, iron and calcium.
There are many types of laxative available over-the-counter. Psyllium containing products are bulk-forming laxatives and are the agents of choice as initial therapy for most forms of constipation. They are also generally the safest laxative agents and have been shown to reduce cholesterol in patients with high cholesterol. Stool-softeners increase the water content of the stool, while irritant/stimulant laxatives have direct action on the intestinal mucosa. Laxatives such as mineral oil are oral and rectal lubricants that retards colonic absorption of fecal water and softens the stool. Chronic use of laxatives, except the psyllium containing preparations, may result in loss of normal bowel function and dependence. Laxatives should be avoided in people with GI obstruction, acute abdominal pain, vomiting or appendicitis as their use can worsen these conditions. Fecal impactions, particularly in the elderly and debilitated population, may require medical treatment.
Hemorrhoids are enlarged veins in the mucous membrane inside or outside of the rectum. Pain does not usually occur with internal hemorrhoids unless a complication such as a fissure also exists. External hemorrhoids can cause pain and itching, and may be accompanied by bleeding. Surgery may be indicated in some cases of hemorrhoids.
Several drug treatments provide symptomatic relief of hemorrhoids. Preparation H suppositories® combine cocoa butter and shark liver oil to form a physical barrier and lubricate the rectal area. In addition to these ingredients, Preparation H creme and ointment® contain glycerin and petrolatum that act as physical barriers and lubricants, and phenylephrine that constricts local blood vessels thus reducing the swelling and itching. Use of topical astringents, such as witch hazel pads, is sometimes soothing. Topical corticosteroids are used to reduce inflammation, itching and swelling. One preparation combines the corticosteroid hydrocortisone with bismuth. The bismuth provides a protective barrier to the irritated area and prevents water loss from the skin. Many products contain local anesthetics such as benzocaine and pramoxine, and are available in multiple forms including foams, suppositories, sprays, creams and ointments. Some products, including some prescription treatments for hemorrhoids, combine an anesthetic with a corticosteroid.
Gallstones are formed in the gallbladder and are made primarily of cholesterol or bilirubin (a byproduct of blood breakdown). They can block the ducts of the gall bladder that lead into the intestine, and can affect gallbladder, liver or pancreatic function. Symptoms may not be present. When symptoms are present, they include sharp right-sided pain up near the rib cage often with associated nausea and vomiting. Surgery is often indicated, although a few oral preparations may assist in the dissolution of the gallstones.
Heartburn is a pain in the chest near the area of the heart but actually results from the esophagus being irritated by stomach acid that is refluxed back into the esophagus. It is referred to as gastroesophageal reflux disease (GERD). It usually occurs after meals or while lying down. Several different treatments both over-the-counter and prescription are available to adequately treat this condition. Antacids neutralize the gastric acid, while other drugs block or decrease gastric acid production. Continuous symptoms indicate the need for medical treatment because the long-term consequences of untreated GERD may be serious.
Peptic Ulcer Disease (PUD)
Peptic ulcer disease (PUD) is a breakdown of the lining of the stomach or the duodenum allowing the underlying tissue to be damaged by gastric acid. Although the cause of the disease is not always known, the bacteria Helicobacter pylori or use of the nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to be involved in many cases. Symptoms are diverse and often relieved by food or antacids, although in some people eating may make the pain worsen. There are several effective drugs available to treat to this disease. In cases where H. pylori is involved, antibiotic treatment is used. Other drugs decrease gastric acid secretion or act by forming a protective cover over the ulcer. Antacids may be used for symptomatic treatment.
Lactose is a sugar present in dairy products that requires an enzyme called lactase to break it up so it can be absorbed and used by the body for energy. Many people lack the enzyme lactase. In fact, 75% of African-Americans, 90% of Asian-Americans and an estimated 30-50 million North Americans are lactose intolerant. When a person does not have this enzyme, drinking milk or eating lactose-containing products will cause diarrhea, and possibly nausea, vomiting and cramps. Symptoms can be avoided by maintaining a lactose-free diet or ingesting commercially prepared lactase prior to eating lactose-containing foods.
Gastroesophageal Reflux Disease (GERD)
Crohn’s disease (CD) is a type of inflammatory bowel disease (IBD) that can affect both the small and large intestine. The lesions are patchy and involve the entire thickness of the intestine most often in the ileum. CD is a chronic condition that may recur at irregular intervals. The most common symptoms are abdominal pain and diarrhea along with generalized weakness, fever, loss of appetite and weight loss. There are several drugs available that can help control CD. These include oral or rectal forms of aminosalicylates such as sulfasalazine and mesalamine, corticosteroids, immune modifiers such as azathioprine and methotrexate, and certain antibiotics. Certain patients with resistant forms of CD may require surgery.
Infliximab (Remicade®, Centocor) is new treatment sometimes used for people with moderate to severe CD that is resistant to the traditional forms of therapy. It may also be used in CD complicated by the presence of fistulas. Infliximab is given by an intravenous infusion and contains antibodies to TNF-alpha. TNF-alpha is involved in the inflammatory process and appears to be elevated in people with CD. The long-term safety of this treatment has not been established.
Maintenance of proper nutrition is important in the medical treatment of CD because poor absorption in the presence of a decreased appetite may lead to depletion of nutrients. Although people with UC may require chronic drug treatment, they generally lead a normal, productive life. There is no cure currently available, however research into new forms of treatment offers hope for improved therapy.
The presence of CD increases the risk for colon cancer. An annual colonoscopy is often recommended as a screening mechanism depending on other risk factors, particularly any evidence of precancerous tissue. There is a currently great research effort to define chemopreventive agents for colon cancer as well as many other types of cancer. Chemoprevention is the attempt to use natural and synthetic compounds to interfere at the early stages of cancer, before invasive disease begins.
Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD). Diagnosis is generally made by history, visualization of the intestine through sigmoidoscopy or colonoscopy, and examination of tissue biopsies by a pathologist. In UC only the lining of the colon (the mucosa) is inflamed and the lesions are symmetric in the affected area. Clinical manifestations of IBD are diarrhea (sometimes bloody), malaise, cramping, abdominal pain and sporadic fever. Treatment consists of aminosalicylates (given orally or rectally) such as sulfasalazine and mesalamine, corticosteroids, and immune modifiers such as cyclosporine and azathioprine. Occasionally nicotine patches or enemas are used in the treatment of UC. IBD resistant to drug treatment may require surgery.
Maintenance of proper nutrition is important in the medical treatment of UC because poor absorption in the presence of a decreased appetite may lead to depletion of nutrients. Although people with UC may require chronic drug treatment, they generally lead a normal, productive life.
Chronic ulcerative colitis increases the risk for colon cancer. Annual colonoscopy is often recommended as a screening mechanism depending on other risk factors, particularly any evidence of precancerous tissue. There is a currently great research effort to define chemopreventive agents for colon cancer as well as many other types of cancer. Chemoprevention is the attempt to use natural and synthetic compounds to interfere at the early stages of cancer, before invasive disease begins. (See colon cancer below.)
Cancers of the Gastrointestinal System
Colorectal cancer is very common, usually occurring after the age of 50. The existence of polyps (protrusions of tissue from the wall of the bowel into the lumen) generally precedes the development of colorectal cancer. Polyps are painless but can bleed, causing blood to be present in the stool. The progression to cancer usually does not occur until after the age of 40 unless there is a genetic-linked familial disorder. Routine medical examination helps detect colorectal cancer at early stages, thereby improving the likelihood of successful treatment. Simple tests to chemically detect small amounts of blood in the stool that are not visible to the eye can be easily performed in the home.
Both polyps and colon cancer occur much more frequently in Western societies where the diets are low in fruits, vegetables, protein from vegetable sources and fiber. Smoking and drinking alcoholic beverages appear to increase the risk of polyp formation. Evidence suggests that diets high in calcium, folic acid and fiber act as chemopreventive agents, reducing the risk of colorectal cancer. There is evidence that use of some nonsteroidal anti-inflammatory drugs (NSAIDs) prevents polyp progression to cancer in certain people. Other drugs are being tested as chemopreventive agents against colon cancer including urosodiol, a bile acid used in the prevention and treatment of gallstones.
Esophageal cancer is relatively rare in the United States. It is more common in men than in women. The most common presenting symptom is difficulty swallowing. People who regularly consume alcohol or smoke (or both) are at increased risk for the development of esophageal cancer. Untreated gastroesophageal reflux disease (GERD) resulting in chronic irritation to the lower esophagus makes the cells more susceptible to cancer development.
Risk for gastric (stomach) cancer increases with age. Evidence suggests that high salt intake, a diet low in fresh fruits and vegetables, and infection with H. pylori are associated with an increased risk of gastric cancer; whereas diets high in whole grain cereals, carotene, and green tea are associated with a reduced risk of this cancer.
Early detection is often difficult because the symptoms are often vague. They include weakness, fatigue, decreased appetite, indigestion, abdominal pain and bloating. The detection of blood in the stool may indicate gastric cancer, but can also be caused by many other things. People with continuous gastric symptoms should seek medical attention. The IES Medical Group treats a variety of gastric problems with state-of-the-art technology, consider booking an appointment with them today if this is something that interests you.
Pancreatic cancer is more common among males than females, with the peak incidence occurring at 60 years of age. The cause is not known. Cigarette smoking and long-term exposure to some chemicals such as dry cleaning fluids, gasoline or metallurgic fumes, appear to increase the risk of this cancer.
Symptoms of pancreatic cancer are often not present at the early stages. When they occur they are usually generalized such as nausea, loss of appetite, weight loss, and weakness. If cancer has spread to the nearby bile duct, jaundice may be seen as yellowing of the whites of the eyes and skin.
Although pancreatic cancer is generally difficult to treat at this time, research aimed at developing early detection techniques and novel forms of therapy are underway. Other research is aimed at determining the effectiveness of a pancreatic cancer vaccine used in combination with chemotherapy and radiation therapy.