Side Effects of Nexium 40 mg Capsules

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Nexium is the brand name for esomeprazole magnesium, a medication used to treat and heal the effects from gastroesophageal reflux disease (GERD). A 40 mg capsule of Nexium is on the higher end of the dosing scale. It is prescribed at this dose for healing of erosive esophagitis or for reducing symptoms of gastric ulcers caused by medications, according to suggests a high dose of Nexium to be used in the treatment of duodenal ulcers or conditions like Zollinger-Ellison syndrome.

Common Side Effects

According to, the most frequently occurring side effects include headache, nausea, diarrhea, flatulence, abdominal pain, constipation, and dry mouth. These symptoms are considered mild. recommends discussing treatment alternatives with a medical care provider if the mild symptoms are bothersome.

Allergic Reaction

According to, an allergic reaction to Nexium is possible. Signs of allergy include rash, hives, itching, difficulty breathing, tightness in the chest, swelling of the mouth, swelling of the tongue, swelling of the lips or unusual hoarseness. Serious signs of allergy can cause a reaction called anaphylaxis or anaphylactic shock. According to the Mayo Clinic, this reaction can be life-threatening if it is not attended to by a medical professional. Anaphylaxis symptoms can occur shortly after contact with the medication and can progress rapidly. The most life-threatening symptoms include constriction of the airways due to a swollen tongue or throat.

Serious Side Effects identifies other severe side effects of Nexium as chest pain, rapid heartbeat, fever, chills, sore throat, redness of the skin, swelling of the skin, blistering or peeling skin, unusual bleeding or bruising, and unusual fatigue. These side effects are not very common but should be reported to a medical professional immediately.