What is the typical dosage of tranexamic acid and hormonal contraceptives for a woman with Abnormal Uterine Bleeding (AUB)?

Tranexamic Acid and Hormonal Contraceptive Dosing for Abnormal Uterine Bleeding

For women with AUB, tranexamic acid should be dosed at 1,300 mg (two 650 mg tablets) three times daily for a maximum of 5 days during menstruation, not exceeding 3,900 mg per day, while combined oral contraceptives should be dosed as one pill daily continuously or in a standard 21/7 cyclic regimen. 1, 2, 3

Tranexamic Acid Dosing Protocol

The standard regimen is 1,300 mg orally three times daily (total 3,900 mg/day) taken only during menstruation for 4-5 days, starting from the first day of bleeding. 1, 2, 4

• Alternative dosing ranges from 3-4 grams daily in divided doses, with some protocols using 1,000 mg three to four times daily during menses 1, 2, 5
• A weight-based approach of 30-50 mg/kg/day in divided doses may be used, but should not exceed 3-4 grams daily 1
• For perimenopausal women, a practical titration strategy starts at 500 mg twice daily, gradually increasing to 1,000 mg 3-4 times daily as needed, staying within the 4-gram maximum 1

Critical Dosing Considerations

• Never exceed 3-4 grams daily, as higher doses (≥4g/24h) significantly increase seizure risk 1, 6
• Tranexamic acid is taken intermittently only during menstruation, not continuously throughout the cycle 2, 4
• Renal impairment requires dose reduction since tranexamic acid is 95% renally excreted unchanged 6, 1

Hormonal Contraceptive Dosing for AUB

Combined Oral Contraceptives (COCs)

Standard dosing is one pill daily, either in a continuous regimen or traditional 21/7 cyclic pattern, with continuous use often preferred for better bleeding control. 3, 5

• For acute heavy bleeding, a multidose regimen can be used: one COC pill three times daily for 7 days, then tapered 3
• Any monophasic combined oral contraceptive containing 30-35 mcg ethinyl estradiol is appropriate 3, 5

Progestin-Only Options

• Continuous oral progestins: norethindrone 5 mg daily continuously (not luteal phase dosing, which is ineffective) 3, 5
• Levonorgestrel intrauterine system (LNG-IUS): 52 mg device releasing 20 mcg/day provides the most effective medical treatment, reducing menstrual blood loss by 96% at 12 months 7, 4, 5

Comparative Efficacy Hierarchy

Medical treatments for AUB rank in efficacy as follows: LNG-IUS > tranexamic acid > combined oral contraceptives > continuous progestins > NSAIDs. 2, 5

• Tranexamic acid reduces menstrual blood loss by 26-60%, significantly more than NSAIDs, luteal phase progestins, or etamsylate 2, 4
• The LNG-IUS is superior to all oral options but may cause amenorrhea (44% of users), which some patients find unacceptable 4, 5
• Tranexamic acid can be combined with NSAIDs (mefenamic acid 500 mg or ibuprofen) for additive effect 3, 8

Absolute Contraindications to Tranexamic Acid

• Active thromboembolic disease (DVT, PE, stroke) 1, 6, 2
• History of thrombosis or thromboembolism 6, 2
• Known hypersensitivity to tranexamic acid 1, 6

Relative Contraindications Requiring Caution

• Concurrent use of hormonal contraceptives with tranexamic acid increases thrombotic risk and requires careful risk-benefit assessment 6
• Atrial fibrillation 1
• Known thrombophilia 1
• History of seizures 1, 6
• Renal impairment (requires dose adjustment, not absolute contraindication) 1, 6

Critical Safety Warning: Combined Use

The FDA label explicitly warns that combined use of tranexamic acid with hormonal contraceptives increases thromboembolic risk, and patients should use effective alternative (nonhormonal) contraception during tranexamic acid therapy. 6

This creates a clinical dilemma: both treatments are effective for AUB, but their combination increases thrombotic risk. The practical approach is:

• For women requiring both antifibrinolytic and hormonal therapy, prioritize LNG-IUS (local progestin effect with minimal systemic absorption) combined with tranexamic acid 7, 5
• If oral hormones are necessary, use them alone without tranexamic acid, or use tranexamic acid alone with NSAIDs 3, 8
• Never combine systemic hormonal contraceptives with tranexamic acid in women with additional thrombotic risk factors (obesity, smoking, age >35, thrombophilia) 6

Common Clinical Pitfalls

• Prescribing luteal phase progestins (days 14-28) is ineffective for AUB; progestins must be given continuously for 21+ days 7, 5
• Exceeding the 4-gram daily maximum of tranexamic acid risks neurotoxicity and seizures 1, 6
• Failing to assess renal function before prescribing tranexamic acid, leading to drug accumulation 6, 1
• Prescribing tranexamic acid continuously throughout the cycle rather than only during menstruation, unnecessarily increasing thrombotic exposure 2, 4