The adverse effects reported most frequently with omeprazole and other proton-pump inhibitors have been headache, diarrhea and skin rashes; sometimes it is severe enough to require discontinuation of treatment. Other effects include pruritus, dizziness, fatigue, constipations, nausea and vomiting, flatulence, abdominal pain, arthralgia and myalgia, urticaria and dry mouth. Isolated cases of photosensitivity, bullous eruption, erythema multiforme, angioedema, and anaphylaxis have been reported. Effects on the CNS include occasional insomnia, somnolence and vertigo; reversible confusional states, agitation, depression and hallucinations have occurred in severely ill patients. Raised liver enzymes and isolated cases of hepatitis, jaundice and hepatic encephalopathy, have been reported. Other adverse effects reported rarely or in isolated cases include paresthesia, blurred vision, alopecia, stomatitis, sweating, taste disturbances, peripheral edema, malaise, hyponatremia, blood disorders (including agranulocytosis, leukopenia and thrombocytopenia) and interstitial nephritis.