Recommended Dosage of Primolute N (Norethindrone Acetate)
The recommended dosage of Primolute N (Norethindrone Acetate) is 10 mg daily, taken at the same time each day, with the specific duration depending on the clinical indication. 1, 2
Dosing Guidelines by Indication
For Endometrial Hyperplasia without Atypia
- 15 mg daily for 10 days (from the 16th to the 25th day of the menstrual cycle) for six months 2
- Alternative regimen: 10 mg daily for 10-25 days, starting on the 2nd day of the cycle 1
For Contraception
- One tablet daily, taken at the same time every day, with continuous administration without interruption between pill packs 3
- For combination with ethinyl estradiol: 1 pill daily for 21 days followed by 1 week of no tablets (for teens >15 years and adults) 4
For Hormone Replacement Therapy
- For post-pubertal women with premature ovarian insufficiency: 10 mg daily for 12-14 days per month when used in sequential regimens 4
- For continuous regimens: minimum of 1 mg daily 4
Important Clinical Considerations
Contraindications
- Pregnancy (Category X) 4
- Active or history of arterial thromboembolic disease 4
- Breast cancer or other hormone-sensitive cancers 4
- Undiagnosed genital bleeding 4
- Hepatic disease or tumors 4
- Deep vein thrombosis or thromboembolic disease 4
Common Adverse Effects
- Central nervous system: headache, depression, mood changes 4
- Endocrine: breast pain, irregular menstruation, breakthrough bleeding 4
- Gastrointestinal: abdominal pain, nausea, vomiting 4
- Genitourinary: urinary tract infections, abnormal uterine bleeding 4
Monitoring Requirements
Drug Interactions
- Reduced efficacy with: antibiotics, anticonvulsants, St. John's wort 4
- Potential interactions with: anticoagulants, barbiturates, protease inhibitors 4
Special Populations
Breastfeeding
- World Health Organization recommends avoiding breastfeeding if possible as infant risk cannot be ruled out 4
Pediatric Use
- Safety and efficacy not established before menarche 4
Extended Use Considerations
- When used in combination with ethinyl estradiol, a 24-day regimen (versus 21-day) may be associated with fewer intracyclic bleeding days and fewer total bleeding/spotting days 5
- For postmenopausal symptoms, low-dose combinations with ethinyl estradiol (0.5 mg/2.5 μg) have shown efficacy in reducing vasomotor symptoms 6