Some of these side effects may occur when taking this medication; they are as follows; Headache or abdominal pain may occur. However, if these symptoms do persist or worsen, it is best then to speak with your doctor.
Tell your doctor right away if you have any serious side effects, including: symptoms of a low magnesium blood level (such as unusually fast/slow/irregular heartbeat, persistent muscle spasms, seizures), signs of lupus (such as rash on nose and cheeks, new or worsening joint pain).
This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to a type of bacteria. Do not use anti-diarrhea or opioid medications if you have any of the following symptoms because these products may make them worse. Tell your doctor right away if you develop: persistent diarrhea, abdominal or stomach pain/cramping, fever, blood/mucus in your stool.
Rarely, proton pump inhibitors (such as esomeprazole) have caused vitamin B-12 deficiency. The risk is increased if they are taken every day for a long time (3 years or longer). Tell your doctor right away if you develop symptoms of vitamin B-12 deficiency (such as unusual weakness, sore tongue, or numbness/tingling of the hands/feet).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.