Lansoprazole is generally well tolerated. At large doses and prolonged use it may stimulate ECL cell growth (enterochromaffin-like-cells). In long-term use, the patient need to be cautious of the excessive growth of bacteria in digestive system.
Sometimes side effects that may occur such as headache, diarrhea, abdominal pain, dyspepsia, nausea, vomiting, dry mouth, constipation, bloating, dizziness, skin rash, urticaria and pruritus.
There is a temporary elevation in liver function test values and will be normal again.
Occasional arthralgia, peripheral edema and depression.
Although it is rare, it has been reported that there are changes in hematological numbers (such as thrombocytopenia, eosinophilia, leukopenia).