Adverse effects of proton-pump inhibitors include gastrointestinal disturbances (including diarrhoea, nausea and vomiting, constipation, flatulence, abdominal pain), headache, hypersensitivity reactions (including rash, urticaria, angioedema, bronchospasm), pruritus, dizziness, peripheral edema, muscle and joint pain, malaise, blurred vision, depression and dry mouth.