Table 109-1 Drugs Definitively Reported to Cause Isolated Thrombocytopeniaa Abciximab Digoxin Acetaminophen Eptifibatide Acyclovir Hydrochlorothiazide Aminosalicylic acid Ibuprofen Amiodarone Levamisole Amphotericin B Octreotide Ampillicin Phenytoin Carbamazepine Quinine Chlorpropamide Rifampin Danazol Tamoxifen Diatrizoate meglumine (Hypaque Meglumine) Tirofiban Trimethoprim/sulfamethoxazole Diclofenac Vancomycin a Drugs that preceded thrombocytopenia and full recovery occurred after drug discontinuation, but recurred with re-introduction of the drug, and other causes, including other drugs were excluded. Source: Data from George and colleagues, . Classic drug-dependent antibodies are antibodies that react with specific platelet surface antigens and result in thrombocytopenia only when the drug is present. . | Chapter 109. Disorders of Platelets and Vessel Wall Part 4 Table 109-1 Drugs Definitively Reported to Cause Isolated Thrombocytopenia Abciximab Digoxin Acetaminophen Eptifibatide Acyclovir Hydrochlorothiazide Aminosalicylic acid Ibuprofen Amiodarone Levamisole Amphotericin B Octreotide Ampillicin Phenytoin Carbamazepine Quinine Chlorpropamide Rifampin Danazol Tamoxifen Diatrizoate meglumine Hypaque Meglumine Tirofiban Trimethoprim sulfamethoxazole Diclofenac Vancomycin Drugs that preceded thrombocytopenia and full recovery occurred after drug discontinuation but recurred with re-introduction of the drug and other causes including other drugs were excluded. Source Data from George and colleagues http jgeorge. Classic drug-dependent antibodies are antibodies that react with specific platelet surface antigens and result in thrombocytopenia only when the drug is present. Many drugs are capable of inducing these antibodies but for some reason they are more common with quinine and sulfonamides. Drug-dependent antibody binding can be demonstrated by laboratory assays showing antibody binding in the presence of but not without the drug present in the assay. The thrombocytopenia typically occurs after a period of initial exposure median length 21 days or upon reexposure and usually resolves in 7-10 days after drug withdrawal. The thrombocytopenia caused by the platelet Gpllbllla inhibitory drugs such as abciximab differs in that it may occur within 24 hours of initial exposure. This appears to be due to the presence of naturally occurring antibodies that cross-react with the drug bound to the platelet. Heparin-Induced Thrombocytopenia Drug-induced thrombocytopenia due to heparin differs from that seen with other drugs in two major ways. 1 The thrombocytopenia is not usually severe with nadir counts rarely 20 000 pL. 2 Heparin-induced thrombocytopenia HIT is not associated with bleeding and in fact markedly increases the risk of thrombosis. HIT results from .
