Ranitidine thrombocytopenia with

A 66-year-old man with schizophrenia took zuclopenthixol 10 mg tds for 18 days and developed a mild leukopenia (2.9 x 109/1) and thrombocytopenia (109 x 109/1). He was asymptomatic, with no evidence of infection or a bleeding tendency. Zuclopenthixol was withdrawn, without any change in the rest of his drug therapy (glibenclamide 5 mg tds, biperiden 2 mg bd, oxazepam 10 mg tds, dipyridamole 75 mg tds, and ranitidine 150 mg/day). The leukocyte and platelet counts rose over the next 5 days. 

Ranitidine is generally well tolerated in therapeutic doses. Ranitidine has less central nervous system (CNS) penetration, endocrine effects, and cardiovascular effects than cimetidine. Reported CNS effects associated with ranitidine include hallucinations, depression, delirium, headaches, dystonia, and choreoathetosis. Cardiac arrest during infusion, bradycardia, and progressive AV block with syncope have been reported in association with ranitidine. Abnormal liver enzymes, interstitial nephritis, parotitis, leukopenia, granulocytopenia, thrombocytopenia, pancytopenia, eosinophilia, vasculitis, dermatitis, toxic epidermal necrolysis, sexual impotence, gynecomastia, and polymyositis have also been reported in association with ranitidine therapy. 

Cimetidine inhibits the activity of the liver enzymes concerned with the metabolism of phenytoin, thus allowing it to accumulate in the body and, in some instances, to reach toxic concentrations. Famotidine, nizatidine and ranitidine normally do not affect these enzymes. Agranulocytosis and thrombocytopenia are relatively rare manifestations of bone marrow depression caused by both phenytoin and the Hj-receptor antagonists. 

Reports are inconsistent. Cimetidine and famotidine have been reported to increase cielosporin levels, whereas in other studies cimetidine, famotidine and ranitidine have been reported to not affect cielosporin levels. Both cimetidine and ranitidine have been reported to cause an increase in serum creatinine levels, in some but not all studies, but this may possibly not be a reliable indicator of increased nephrotoxicity. Isolated cases of thrombocytopenia and hepatotoxicity have been reported with ranitidine and cielosporin. 

A report describes thrombocytopenia in a man taking ciclosporin after a kidney transplant who was given ranitidine. Another patient experienced hepatotoxicity while taking ciclosporin with ranitidine. ... 

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