title: Interaction between hormone replacement therapy preparations and oral anticoagulant therapy.
abstract: There is limited information regarding the interaction of hormone replacement therapy (HRT) and oral anticoagulants. Following the acute over-anticoagulation of two women shortly after the initiation of tibolone, we have undertaken a retrospective review of anticoagulated women to determine if the dose of oral anticoagulants and quality of anticoagulant control are affected by the introduction of HRT. We demonstrate that acute over-anticoagulation consistently occurs following the commencement of tibolone and requires anticoagulant dose modification to re-establish target international normalised ratio (INR). In contrast, non-tibolone HRT preparations do not consistently alter anticoagulant control or dose requirements.
authors.affiliation: Department of Haematology, Glasgow Royal Infirmary, Macewen Building, Castle Street, Glasgow G4 0SF, Scotland, UK.
authors.forename: L A
authors.initials: LA
authors.lastname: McLintock
authors.forename: A
authors.initials: A
authors.lastname: Dykes
authors.forename: R C
authors.initials: RC
authors.lastname: Tait
authors.forename: I D
authors.initials: ID
authors.lastname: Walker
mesh_terms: D000284:Administration, Oral; D000925:Anticoagulants / Q000008:administration & dosage; D000075202:Contraindications; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D020847:Estrogen Receptor Modulators / Q000008:administration & dosage; D005260:Female; D020249:Hormone Replacement Therapy; D006801:Humans; D019934:International Normalized Ratio; D009652:Norpregnenes / Q000008:administration & dosage; D010630:Phenindione / Q000008:administration & dosage; D014859:Warfarin / Q000008:administration & dosage
chemical_list: D000925:Anticoagulants; D020847:Estrogen Receptor Modulators; D009652:Norpregnenes; D010630:Phenindione; D014859:Warfarin; C027385:tibolone