How do I write a prescription for Lo Loestrin Fe (notethindrone acetate and ethinyl estradiol)?

How to Write a Prescription for Lo Loestrin Fe

Write the prescription as: "Lo Loestrin Fe (norethindrone acetate 1 mg/ethinyl estradiol 10 mcg), Dispense: #28 tablets per pack, Sig: Take 1 tablet by mouth daily at the same time each day for 28 days, then start a new pack immediately without interruption." 1

Patient Eligibility

• Approved for women ≥15 years of age for contraception 1
• Safety and efficacy have not been established in pre-menarchal patients 1

Pre-Prescription Requirements

Before writing the prescription, you must complete the following baseline assessments:

• Confirm negative pregnancy status using urine pregnancy test or clinical assessment 1, 2
• Measure baseline blood pressure and document the value 1, 2
• Screen for absolute contraindications including 1:
  • Active or history of thromboembolic disease (DVT, PE, stroke, MI)
  • Breast cancer or other estrogen/progestin-sensitive cancers
  • Undiagnosed abnormal uterine bleeding
  • Hepatic disease or hepatic tumors
  • Current pregnancy
  • Age ≥35 years with smoking history
  • Uncontrolled hypertension
  • Cerebrovascular or coronary artery disease

Prescription Format

Standard prescription should include 1:

• Drug name: Lo Loestrin Fe (norethindrone acetate 1 mg/ethinyl estradiol 10 mcg with ferrous fumarate)
• Quantity: Dispense 28 tablets per pack
• Directions: Take 1 tablet by mouth daily at the same time each day for 28 days
• Refills: Specify number of refills (typically 11 for one year)
• Special instructions: Start new pack immediately after finishing previous pack without interruption

Ongoing Monitoring Requirements

At follow-up visits, assess 1:

• Blood pressure measurement at each visit
• Changes in health status, particularly cardiovascular or thromboembolic symptoms
• Compliance with daily dosing regimen
• Any breakthrough bleeding patterns (though Lo Loestrin Fe formulations demonstrate favorable bleeding profiles compared to other low-dose options) 3, 4

Critical Drug Interactions

Document and counsel patients about major interactions requiring alternative contraception or dose adjustment 1:

• Antibiotics (rifampin, certain cephalosporins, macrolides, penicillins, tetracyclines)
• Anticonvulsants (phenytoin, carbamazepine, topiramate, barbiturates)
• HIV protease inhibitors
• St. John's wort
• Hepatitis C antivirals (boceprevir, telaprevir)
• Modafinil
• Griseofulvin

Common Prescribing Pitfalls to Avoid

Never prescribe without 1:

• Confirming negative pregnancy status first
• Measuring and documenting baseline blood pressure
• Screening for cardiovascular risk factors, especially in women ≥35 years who smoke

Emphasize to patients 5:

• The importance of taking the pill at the same time every day to maximize efficacy
• If one pill is missed (<24 hours late): take it as soon as remembered
• If one pill is missed (24-48 hours): take the most recent missed pill, use backup contraception for 7 days
• If two or more pills are missed (>48 hours): take the most recent missed pill, use backup contraception for 7 days, and consider emergency contraception if unprotected intercourse occurred in the previous 5 days

Withdrawal Bleeding Expectations

• If withdrawal bleeding does not occur within 3 weeks of starting therapy, perform pregnancy testing 2
• The 24-day active hormone regimen in Lo Loestrin Fe formulations is associated with fewer total bleeding/spotting days compared to traditional 21-day regimens 3