Fluoxetine Induced Menorrhagia

AIMS: Selective serotonin reuptake inhibitors play important role in treatment of various psychiatric disorders. Commonly prescribed SSRIs include Sertraline and Fluoxetine. Fluoxetine has a high level of serotonin reuptake inhibition and a prolonged half-life. SSRIs can increase the risk of gastro-intestinal bleeding. A recent systematic review suggested an increased risk of intracranial bleeding in patients taking SSRIs. Psychiatric patients on SSRIs may present with menstrual disorders. Currently, there is limited information on its effect on menstrual cycle. The aim of this study is to explore the possible association between Fluoxetine and menorrhagia. METHODS: Case Study ,29 years old, female patient, diagnosed with mixed anxiety and depression ICD-10 F41.2. No previous medical history of menstrual disorders. She started sertraline medications, initial dose of 50 mg, which was gradually titrated to 150 mg. After 12 weeks, Sertraline was discontinued due to limited effectiveness and was started on fluoxetine 20 mg. Dose was gradually titrated to 40 mg, Menorrhagia for 14 days was reported. Physical examination was unremarkable. A period of discontinuation of fluoxetine attempted leading to partial resolution of symptoms. However, 2 weeks later after careful examination of the risks and benefits, Fluoxetine was re-introduced. A trial of Tranexamic Acid 1 gm t.ds. for five days at the expected date of menstruation was initiated. RESULTS: Patient had no changes in her scheduled menstrual bleeding when she was using Sertraline. However, after 2 weeks of initiating 20 mg of fluoxetine the patient reported heavy prolonged bleeding with estimated 100% increase in volume and duration of the scheduled bleeding. Dose titration to 40 mg, led to further increase in the severity and duration of the bleeding. Changes in platelet function tests was reported 3 months after initiation of treatment; however, the results remained within the normal range. Tranexamic Acid 1 gm t.ds. for five days led to significant reduction in the severity and duration of bleeding. CONCLUSION: Using the WHO-UMC Causality Categories to explore association of the study findings, it is likely/ probable that Fluoxetine is associated with menorrhagia. A likely dose effect association was observed. Possible explanation of the increased risk of bleeding relates to its inhibitory action on platelet aggregation. However, Fluoxetine can be used safely for long term when Tranexamic acid was add. Tranexamic Acid has primary effect on thrombin generation; Its secondary effects is on improving platelet function and coagulation factors, leading to successful reduction in duration and severity of the bleeding.