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Everyone has probably
experienced heartburn at least once in their lifetime. For many people,
this happens infrequently and can be related to certain foods or activities
and doesn’t cause too much trouble. Television, radio and print advertising
spend a lot of time promoting over-the-counter remedies for those persons
with only infrequent symptoms. For some people, however, these symptoms
occur frequently and disrupt their ability to carry out their daily routine.
Their symptoms may also be more severe and include nausea, regurgitation
of stomach contents leaving an acid or bitter taste in the mouth, sore
throat, or even asthma. Many times they’ve tried all the over-the-counter
remedies without the desired degree of symptom relief. This is when a
visit to the doctor can be helpful.
First, some common
ailments requiring specific treatment (such as peptic ulcers) must be
excluded. This typically requires an evaluation of the upper gastrointestinal
tract. The two common methods currently being used are a barium test (upper
GI series) and an endoscopy (Esophagogastroduodenoscopy or EGD). These
tests, particularly the EGD, may detect injury to the lining (called the
mucosa) of the esophagus from gastroesophageal reflux disease or GERD.
If injury is observed, this indicates the presence of erosive GERD. However,
many patients will have the symptoms of GERD without having injury to
the esophageal lining and can be diagnosed with nonerosive GERD. Sometimes
a specific test, called a 24 hour pH monitoring, will be used to look
for abnormal amounts of acid in the lower esophagus to confirm the diagnosis
of GERD.
Why do people get
GERD? The normal stomach makes a lot of acid and pepsin (an enzyme which
helps with breaking down food). Normally, the lining of the stomach can
resist the action of this acid and pepsin. If not, then a peptic ulcer
may develop. We now know that a bacteria called Helicobactor pylori is
an important factor in allowing injury to occur to the stomach lining
by disrupting this normal mucosal defense and if peptic ulcers are seen
in patients with Helicobacter pylori infections in their stomach, the
current treatment includes antibiotics to clear the infection in addition
to direct treatment of the ulcer by suppressing acid secretion.
Does a similar process
occur in the esophagus? Not exactly. The lining of the esophagus is not
designed to resist the actions of acid and pepsin to begin with, so injury
can occur without the presence of some “scapegoat” like Helicobacter pylori.
The esophagus “defends” itself by creating a barrier to acid/pepsin reflux
(the lower esophageal sphincter), squeezing out the refluxed acid (peristalsis),
and by neutralizing the remaining acid (swallowed saliva). As you can
imagine, everyone has reflux. If these esophageal defense mechanisms are
working properly, it’s no big deal. If one or more of these defense mechanisms
fails, GERD is likely to occur.
This also tells us
how we can treat GERD. You can fix the lower esophageal sphincter (a band
of muscle at the lower end of the esophagus), but this requires some major
surgery. Or, you can give drugs which either improve peristalsis (the
normal coordination of muscles in the esophagus which move food from the
mouth to the stomach) or suppress/neutralize acid secretion. Drugs which
improve peristalsis are called prokinetic agents (and usually help the
lower esophageal sphincter muscle squeeze a little harder as well). The
older prokinetic agents usually didn’t work well enough or had too many
side effects. Acid suppression can be achieved by taking antacids which
directly neutralize the acid (sort of a commercial equivalent of “spit”),
but most GERD patients can’t drink enough to block their symptoms. Drugs
which block acid secretion include “H2 blockers” (named for their ability
to block histamine, which is produced locally in the stomach, from interacting
with it’s receptor, the Histamine Type 2 receptor, and stimulate acid
secretion) and proton pump inhibitors (named for their ability to block
the enzyme which “pumps” acid, or protons, into the stomach).
Currently, we are
enrolling patients in clinical trials to test some of the newer prokinetic
agents and determine their most appropriate use in patients suffering
with GERD.
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