Omeprazole is well tolerated and adverse reactions have generally been mild and reversible. Skin rash, urticaria and pruritus have been reported. Usually resolving after discontinuation of treatment. In addition photosensitivity, bullous eruption, erythema multiforme, angioedema and alopecia have been reported in isolated cases. Diarrhoea and headache have been reported and may be severe enough to require discontinuation of therapy in a small number of patients. In the majority of cases the symptoms resolved after discontinuation of therapy. Other gastrointestinal reactions have included constipation, nausea/vomiting, flatulence and abdominal pain. Dry mouth, stomatitis and candidiasis have been reported as isolated cases. Paraesthesia has been reported. Dizziness, light headedness and feeling faint have been associated with treatment, but all usually resolve on cessation of therapy. Also reported are somnolence, insomnia and vertigo. Reversible mental confusion, agitation, depression and hallucinations have occurred predominantly in severely ill patients. Arthritic and myalgic symptoms have been reported and have usually resolved when therapy is stopped. In isolated cases, the following have been reported: blurred vision, taste disturbance, peripheral oedema, increased sweating, gynaecomastia, leucopenia, thrombocytopenia, agranulocytosis, pancytopenia, anaphylactic shock, malaise, fever, bronchospasm, encephalopathy in patients with pre-existing severe liver disease, hepatitis with or without jaundice, rarely interstitial nephritis and hepatic failure. Increases in liver enzymes have been observed.
