Antacids are acid reducing medications that directly lower the acidity of stomach contents.
They are used to treat conditions like gastroesophageal reflux disorder, or
GERD, and peptic ulcer disease, or (PUD).
When combined with antiflatulent medications like simethicone, they also help decrease gas
production, which provides comfort and relief to clients experiencing gas or bloating.
Antacids can be made up of aluminum, magnesium, calcium or sodium compounds. Common antacid
medications include: aluminum hydroxide, aluminum hydroxide and simethicone, magnesium hydroxide,
magnesium hydroxide and aluminum hydroxide, magnesium trisilicate and aluminum hydroxide,
magaldrate, calcium carbonate, calcium carbonate with magnesium hydroxide, and sodium bicarbonate.
Now when antacids are taken, the medication reacts with gastric acid
and results in the production of neutral or low-acidity salts that increase the gastric pH.
Additionally, the enzyme pepsin that normally helps digest protein is also inactivated. The
outcomes of these reactions are a decrease in gastric acidity, enhanced mucosal protection
and a reduction of the symptoms associated with GI conditions such as GERD and PUD.
Antacids can cause several side effectsIf they are taken for an extended period of time,
they may alter aluminum, calcium, sodium and phosphate levels. Other general side effects
of antacids include belching, constipation, flatulence, diarrhea and gastric distention.
Since all antacids increase gastric pH and can potentially bind with other drugs,
absorption and effectiveness of medications taken along with antacids can be affected.
For example, they can increase oral absorption of medications that are weak bases, such as
quinidine, an antiarrhythmic and anti-parasite medication; and decrease the oral absorption of
medications that are weak acids, such as warfarin sodium. Also, antacids can chelate, or bond,
other medications in the GI tract, resulting in new complexes that are not absorbable.
This is especially common with medications such as tetracyclines, a class of antibiotics. So,
spacing out antacids from other medications by 1-2 hours, or as prescribed, is important.
Depending on the medication’s compound,
side effects can vary amongst different types of antacids.
For aluminum based antacids, constipation, hypophosphatemia, which can manifest as anorexia,
malaise, tremors and muscle weakness; and aluminum toxicity with prolonged use can occur.
A common side effect of magnesium based antacids is diarrhea.
However, when combined with an aluminum based compound, it is less likely to occur.
Calcium based antacids can cause hypercalcemia and metabolic alkalosis,
and sodium bicarbonate antacids have the potential to worsen hypertension
and the risk for heart failure, largely because of the sodium content it contains.
Nursing Considerations & Client Education There are several important contraindications
that should be considered before administering antacids to clients.
Aluminum compounds for example are contraindicated in clients with low serum phosphate levels,
because the addition of aluminum can lead to hypophosphatemia. Magnesium compounds should
be avoided in clients with abdominal pain, nausea and vomiting, diarrhea, severe renal dysfunction,
fecal impaction, rectal bleeding and if they have a colostomy or ileostomy in place.
Calcium compounds are contraindicated in clients with hypercalcemia and hypercalciuria,
severe renal disease, renal calculi, dehydration and GI bleeding or obstruction. Finally,
sodium compounds should be used with caution in clients with hypertension and heart failure.
Antacids should be administered and taken on a regular schedule and for maximum therapeutic
benefit, it should raise the gastric pH to above 5. Clients should be educated to chew
antacids tablets well and follow it with water or milk, if not contraindicated. For
antacids that come in liquid form, be sure it’s shaken before taking. If you’re administering an
antacid via nasogastric tube, or NGT, be sure to flush with water following the medication.
The safety of antacid use in lactating women hasn’t been established yet,
so it should be used with caution in this client population. Finally, just as with all medications,
it’s important to keep it out of reach of children and to be sure your client has
consulted their primary care provider before beginning this over-the-counter regimen.
All right, as a quick recap, antacids are acid reducing medications that directly
lower the acidity of stomach contents. They are used to treat conditions like
gastroesophageal reflux disorder, or GERD, and peptic ulcer disease, or PUD.
When combined with medications like simethicone, they also act as an antiflatulent.
Antacids can be made up of aluminum, magnesium,
calcium or sodium compounds. Depending on the medication’s composition, side effects can
vary amongst different types of antacids, which can include belching, constipation, flatulence,
diarrhea and gastric distention. There are several important contraindications and
client education that should be considered by the nurse before administering antacids to clients.