Thrombotic thrombocytopenic purpura valacyclovir

Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) has occurred in patients with advanced HIV disease and also in allogeneic bone marrow transplant and renal transplant recipients taking valacyclovir at doses of 8 g/day. 

Valacyclovir is generally well tolerated, although nausea, vomiting, or rash occasionally occur. At high doses, confusion, hallucinations, and seizures have been reported. AIDS patients who received high-dosage valacyclovir chronically (ie, 8 g/d) had an increased incidence of gastrointestinal intolerance as well as thrombotic thrombocytopenic purpura and hemolytic-uremic syndrome this dose was associated with confusion and hallucinations in transplant patients. 

Like acyclovir, valacyclovir is a well-tolerated drug. The most common adverse effects of valacyclovir are headache and nausea. Other adverse events associated with valacyclovir administration include vonuting, weakness, cUzziness, and abdoiifinal pain. Thrombotic thrombocytopenic purpura/ hemolytic ureiiuc syndrome has also been reported in a few patients after high doses of valacyclovir, as has confusion, hallucinations, and nephrotoxicity (Curran and Noble, 2001 Perry and Faulds, 1996). 

Rivaud E, Massiani M-A, Vincent F, Azoulay E,Couderc L-J.Valacyclovir hydrochloride therapy and thrombotic thrombocytopenic purpura in an HIV-infected patient. Arch Int Med 2000 160 1705-1706. 

Bell, WR, Chulay JD, Feinberg JE. Manifestations resembling thrombotic microangiopathy in patients with advanced human immunodeficiency virus (HIV) disease in a cytomegalovirus prophylaxis trial (ACTG 204). Medicine 1997 76 369-380. Rivaud E, Massiani M-A, Vincent F, Azoulay E, Couderc L-J. Valacyclovir hydrochloride therapy and thrombotic thrombocytopenic purpura in an HIV-infected patient. Arch Int Med 2000 160 1705-1706. 

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