Drugs Induced Thrombocytopenia


     Immune thrombocytopenia (ITP) is the commonest blood disorder that causes thrombocytopenia or low platelet count. Apart from ITP, many drugs can cause thrombocytopenia. Some drugs like anticancer drugs and valproic acid cause dose depended decrease in the number of platelets by myelosuppression. Drugs may also cause thrombocytopenia by immunological mechanisms. Immunological drug-induced thrombocytopenia can be caused by the following two mechanisms.

  1. This is caused by drug depended binding of Fab part of the pathological IgG with the platelets, causing their destruction. This is exemplified the quinidine group of drugs, and seen with many different types of drugs. Fc portion of the IgG molecule is not involved in the binding
  2. In this type the Fab portion of the pathological IgG binds to platelet factor 4 (PF4).When complexed with heparin or other drugs, the Fc portion of the IgG molecule bind to platelet receptors causing platelet activation. Since Fc portion of the IgG is bound to the platelets, they are not available to the Fc receptors of the reticulo-endothelial cells. This may explain, why severe thrombocytopenia is rare in patients with HIT.
List of drugs that causes thrombocytopenia
(anti-neoplastic drugs are not included)

  • Quinine/Quinidine group
    • Quinine
    • Quinidine

  • Heparin
    • Regular unfractionated heparin
    • Low molecular weight heparin

  • Gold salts
  • Antimicrobials
    • Antimony containing drugs
      • Stibophen
      • Sodium stibogluconate
    • Cephalosporins
      • Cephamandazole
      • Cefotetan
      • Ceftazidime
      • Cephalothin
    • Ciprofloxacin
    • Clarithromycin
    • Fluconazole
    • Fusidic
    • acid
    • Gentamicin
    • Nilidixic acid
    • Penicillins
      • Ampicillin
      • Apalcillin
      • Methicillin
      • Meziocillin
      • Penicillin
      • Piperacillin
    • Pentamidine
    • Rifampin
    • Sulpha group
      • Sulfamethoxazole
      • Sulfamethoxypyridazine
      • Sulfisoxazole
    • Suramin
    • Vancomycin

  • Anti-inflammatory drugs
    • Acetaminophen
    • Salicylates
      • Aspiring
      • Diflunisal
      • Sodium amiosalicylate
      • Sulfasalazine
    • Diclofenac
    • Fenoprofen
    • Ibuprofen
    • Indomethacin
    • Meclofenamate
    • Mefanamic acid
    • Naproxen
    • Oxyphebutazone
    • Phenylbutazone
    • Piroxicam
    • Sulindac
    • Tolmetin

  • Cardiac medications and diuretics
    • Digoxin
    • Digitoxin
    • Amiodarone
    • Procainamide
    • Alprenolol
    • Oxprenolol
    • Captopril
    • Diazoxide
    • Alpha-methyldopa
    • Acetazolamide
    • Chlorothiazide
    • Chlorthalidone
    • Furosemide
    • Hydrochlorothiazide
    • Sprinolactone

  • Benzodiazepines
    • Diazepam

  • Anti-epileptic drugs
    • Carbamazepine
    • Phenytoin
    • Valproic acid
    H2-antagonists
    • Cimetidine
    • Ranitidine

  • Sulfonylurea drugs
    • Chlorpropamid
    • Glibenclamide

  • Iodinated contrast agents
  • Retinoids
    • Isotretinoin
    • Etretinate

  • Anti-histamines
    • Antazoline
    • Chlorpheniramine

  • Illicite drugs
    • Cocaine
    • Heroin
    • Qunine containment

  • Antidepressants
    • Amitriptyline
    • Desipramine
    • Doxepin
    • Imipramine
    • Mianserine

  • Miscellaneous drugs
    • Tamoxifen
    • Actinomycin-D
    • Aminoglutethimide
    • Danazole
    • Desferrioxamine
    • Levamizole
    • Lidocaine
    • Morphine
    • Papaverine
    • Ticlopidine

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