Interaction between hormone replacement therapy preparations and oral anticoagulant therapy.
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.
McLintock
L A
LA
Department of Haematology, Glasgow Royal Infirmary, Macewen Building, Castle Street, Glasgow G4 0SF, Scotland, UK.
Dykes
A
A
Tait
R C
RC
Walker
I D
ID
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
D000925:Anticoagulants; D020847:Estrogen Receptor Modulators; D009652:Norpregnenes; D010630:Phenindione; D014859:Warfarin; C027385:tibolone