Antacids
Despite the development of potent medications for the treatment of GERD,
antacids remain a mainstay of treatment. Antacids neutralize the acid
in the stomach so that there is no acid to reflux. The problem with antacids
is that their action is brief. They are emptied from the empty stomach
quickly, in less than an hour, and the acid then re-accumulates. The best
way to take antacids, therefore, is approximately one hour after meals
or just before the symptoms of reflux begin after a meal. Since the food
from meals slows the emptying from the stomach, an antacid taken after
a meal stays in the stomach longer and is effective longer. For the same
reason, a second dose of antacids approximately two hours after a meal
takes advantage of the continuing post-meal slower emptying of the stomach
and replenishes the acid-neutralizing capacity within the stomach.
Antacids may be aluminum, magnesium, or calcium based. Calcium-based antacids
(usually calcium carbonate), unlike other antacids, stimulate the release
of gastrin from the stomach and duodenum. Gastrin is the hormone that
is primarily responsible for the stimulation of acid secretion by the
stomach. Therefore, after the direct acid-neutralizing effect of the calcium
carbonate is exhausted, the secretion of acid rebounds. The rebound is
due to the release of gastrin, which results in an overproduction of acid.
Theoretically at least, this increased acid is not good for GERD.
Acid rebound, however, has not been shown to be clinically important.
That is, treatment with calcium carbonate has not been shown to be less
effective or safe than treatment with antacids not containing calcium
carbonate. Nevertheless, the phenomenon of acid rebound is theoretically
harmful. In practice, therefore, calcium-containing antacids such as Tums
and Rolaids are not recommended. The occasional use of these calcium carbonate-containing
antacids, however, is not believed to be harmful. The advantages of calcium
carbonate-containing antacids are their low cost and the calcium they
add to the diet.
Aluminum-containing antacids have a tendency to cause constipation, while
magnesium-containing antacids tend to cause diarrhea. If diarrhea or constipation
becomes a problem, it may be necessary to switch antacids or alternately
use antacids containing aluminum and magnesium.
Histamine antagonists
Although antacids can neutralize acid, they do so for only a short period
of time. For substantial neutralization of acid throughout the day, antacids
would need to be given frequently, at least every hour.
The first medication developed for more effective and convenient treatment
of acid-related diseases, including GERD, was a histamine antagonist,
specifically cimetidine (Tagamet). Histamine is an important chemical
because it stimulates acid production. Released within the wall of the
stomach, histamine attaches to receptors (binders) on the stomach's acid-producing
cells and stimulates the cells to produce acid. Histamine antagonists
work by blocking the receptor for histamine and thereby preventing histamine
from stimulating the acid-producing cells. (Histamine antagonists are
referred to as H2 antagonists because the specific receptor they block
is the histamine type 2 receptor.)
Because histamine is particularly important for the stimulation of acid
after meals, H2 antagonists are best taken 30 minutes before meals. The
reason for this timing is so that the H2 antagonists will be at peak levels
in the body after the meal when the stomach is actively producing acid.
H2 antagonists also can be taken at bedtime to suppress nighttime production
of acid.
H2 antagonists are very good for relieving the symptoms of GERD, particularly
heartburn. However, they are not very good for healing the inflammation
(esophagitis) that may accompany GERD. In fact, they are used primarily
for the treatment of heartburn in GERD that is not associated with inflammation
or complications, such as erosions or ulcers, strictures, or Barrett's
esophagus.
Four different H2 antagonists are available by prescription, including
cimetidine (Tagamet), ranitidine (Zantac), nizatidine (Axid), and famotidine,
(Pepcid). All four are also available over-the-counter (OTC), without
the need for a prescription. However, the OTC dosages are lower than those
available by prescription.
Proton pump inhibitors
The second type of drug developed specifically for acid-related diseases,
such as GERD, was a proton pump inhibitor (PPI), specifically, omeprazole
(Prilosec). A PPI blocks the secretion of acid into the stomach by the
acid-secreting cells. The advantage of a PPI over an H2 antagonist is
that the PPI shuts off acid production more completely and for a longer
period of time. Not only is the PPI good for treating the symptom of heartburn,
but it also is good for protecting the esophagus from acid so that esophageal
inflammation can heal.
PPIs are used when H2 antagonists do not relieve symptoms adequately or
when complications of GERD such as erosions or ulcers, strictures, or
Barrett's esophagus exist. Five different PPIs are approved for the treatment
of GERD, including omeprazole (Prilosec), lansoprazole (Prevacid), rabeprazole
(Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium). PPIs are
best taken an hour before meals. The reason for this timing is that the
PPIs work best when the stomach is most actively producing acid, which
occurs after meals. If the PPI is taken before the meal, it is at peak
levels in the body after the meal when the acid is being made.
Pro-motility drugs
Pro-motility drugs work by stimulating the muscles of the gastrointestinal
tract, including the esophagus, stomach, small intestine, and/or colon.
One pro-motility drug, metoclopramide (Reglan), is approved for GERD.
Pro-motility drugs increase the pressure in the lower esophageal sphincter
and strengthen the contractions (peristalsis) of the esophagus. Both effects
would be expected to reduce reflux of acid. However, these effects on
the sphincter and esophagus are small. Therefore, it is believed that
the primary effect of metoclopramide may be to speed up emptying of the
stomach, which also would be expected to reduce reflux.
Pro-motility drugs are most effective when taken 30 minutes before meals
and again at bedtime. They are not very effective for treating either
the symptoms or complications of GERD. Therefore, the pro-motility agents
are reserved either for patients who do not respond to other treatments
or are added to enhance other treatments for GERD.
Foam barriers
Foam barriers provide a unique form of treatment for GERD. Foam barriers
are tablets that are composed of an antacid and a foaming agent. As the
tablet disintegrates and reaches the stomach, it turns into foam that
floats on the top of the liquid contents of the stomach. The foam forms
a physical barrier to the reflux of liquid. At the same time, the antacid
bound to the foam neutralizes acid that comes in contact with the foam.
The tablets are best taken after meals (when the stomach is distended)
and when lying down, both times when reflux is more likely to occur. Foam
barriers are not often used as the first or only treatment for GERD. Rather,
they are added to other drugs for GERD when the other drugs are not adequately
effective in relieving symptoms. There is only one foam barrier, which
is a combination of aluminum hydroxide gel, magnesium trisilicate, and
alginate (Gaviscon).
Surgery
The drugs described above usually are effective in treating the symptoms
and complications of GERD. Nevertheless, sometimes they are not. For example,
despite adequate suppression of acid and relief from heartburn, regurgitation,
with its potential for complications in the lungs, may still occur. Moreover,
the amounts and/or numbers of drugs that are required for satisfactory
treatment are sometimes so great that drug treatment is unreasonable.
In such situations, surgery can effectively stop reflux.
The surgical procedure that is done to prevent reflux is technically known
as fundoplication and is called reflux surgery or anti-reflux surgery.
During fundoplication, any hiatal hernial sac is pulled below the diaphragm
and stitched there. In addition, the opening in the diaphragm through
which the esophagus passes is tightened around the esophagus. Finally,
the upper part of the stomach next to the opening of the esophagus into
the stomach is wrapped around the lower esophagus to make an artificial
lower esophageal sphincter. All of this surgery can be done through an
incision in the abdomen (laparotomy) or using a technique called laparoscopy.
During laparoscopy, a small viewing device and surgical instruments are
passed through several small puncture sites in the abdomen. This procedure
avoids the need for a major abdominal incision.
Surgery is very effective at relieving symptoms and treating the complications
of GERD. Approximately 80% of patients will have good or excellent relief
of their symptoms for at least 5 to 10 years. Nevertheless, many patients
who have had surgery--perhaps as many as half--will continue to take drugs
for reflux. It is not clear whether they take the drugs because they continue
to have reflux and symptoms or if they take them for symptoms that are
being caused by problems other than GERD. The most common complication
of fundoplication is swallowed food that sticks at the artificial sphincter.
Fortunately, the sticking usually is temporary. If it is not transient,
endoscopic treatment to stretch (dilate) the artificial sphincter usually
will relieve the problem. Only occasionally is it necessary to re-operate
to revise the prior surgery.
Endoscopy
Very recently, endoscopic techniques for the treatment of GERD have been
developed. One type of endoscopic treatment involves suturing (stitching)
the area of the lower esophageal sphincter, which essentially tightens
the sphincter. A second type involves the application of radio-frequency
waves to the lower part of the esophagus just above the sphincter. The
waves cause damage to the tissue beneath the esophageal lining and a scar
(fibrosis) forms. The scar shrinks and pulling on the surrounding tissue,
thereby tightening the sphincter and the area above it.a third type of
endoscopic treatment involves the injection of material into the esophageal
wall in the area of the LES. This increases the pressure in the LES and
prevents reflux.
Endoscopic treatment has the advantage of not requiring surgery. It can
be performed without hospitalization. Since these endoscopic techniques
are new, however, it is not yet clear how effective they are or for how
long they will be effective. More studies with endoscopic treatments are
necessary.
Prevention of transient LES relaxation
Transient LES relaxations appear to be the most common way in which acid
reflux occurs. Although there are available drugs that prevent relaxations,
they have too many side effects to be useful. Much attention is being
directed at the development of drugs that prevent these relaxations without
accompanying side effects.
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