II. Indications: Contraception
- Lactation
-
Estrogen contraindicated
- See Oral Contraceptives
- Age over 35 years old and Tobacco use
- Migraine with Aura (risk of CVA)
- Venous Thromboembolism Risk
III. Contraindications
- Pregnancy
- Breast Cancer or Progestin-sensitive cancer
- Liver neoplasms
- Undiagnosed Abnormal Uterine Bleeding
IV. Mechanism
- No Estrogen
- Progesterone only (activity varies by Progestin type)
V. Precautions
- Must be taken at the same time everyday (within 2 hours)
- Indications to use backup Contraception (e.g. Condoms) for 2 days
VI. Medications
-
Norgestrel 75 mcg
- Activity: Low Estrogenic, moderate progestational, moderate androgenic, moderate endometrial
- Opill
- First Oral Contraceptive available OTC without a prescription (in U.S. 2024)
- Ovrette
- Withdrawn from market in 2005 (for business decisions)
-
Norethindrone 350 mcg
- Activity: low Estrogenic, low progestational, low androgenic, low endometrial
- Micronor, Nor-QD, Nora-BE, Jolivette, Camila or Errin
- Noriday (UK)
- Drospirenone 4 mg (Slynd)
- Activity: Low androgenic
- Released in 2019 in U.S. at $200/month
- Marketed as having more maintained efficacy after a missed pill than Norethindrone
- Does not require back-up Contraception if missed pill is taken within 24 hours
- Risk of Hyperkalemia (anti-mineralcorticoid effect)
- Less unscheduled Abnormal Uterine Bleeding than with other Progesterone only contraceptives
- (2019) Presc Lett 26(10): 58
-
Ethynodiol Diacetate 500 mcg
- Femulen (UK)
-
Levonorgestrel 30 mcg
- Norgeston (UK)
- Microlut (Australia)
-
Desogestrel 75 mcg
- Cerazette (UK)
- References
VII. Adverse Effects: Norgestrel
- Ectopic Pregnancy increased Incidence
- Breakthrough Menstrual Bleeding (up to 50% of patients)
- Responsible for at least two thirds of the patients discontinuing Progestin only Oral Contraceptive
- Consider periodic NSAID for 5 days (Naproxen 500 mg twice daily, Ibuprofen 800 mg three times daily)
- Consider switching to Drospirenone (Slynd), which is associated with less unscheduled Abnormal Uterine Bleeding
- Consider switching to combination Oral Contraceptive
- Other common adverse effects
VIII. Drug Interactions: Norgestrel
- Medications that reduce Norgestrel levels and contraceptive efficacy
- St Johns Wort
- HIV Medications (e.g. Efavirenz)
- Antiepileptic Medications
IX. Efficacy
- High failure rate compared with combination pills
- Consider more effective Progesterone-only options (Mirena IUD, Nexplanon Contraceptive Implant)
- Better efficacy then barrier methods
- Failure rates
- Perfect use: 0.5 to 2% failure rate
- Typical use: 5 to 9% failure rate
X. References
- (2024) Presc Lett 31(1): 1
- Torro (2024) Am Fam Physician 109(1): 90-1 [PubMed]
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Related Studies
| nora-be (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| NORA-BE TABLET | Generic | $0.15 each |
| camila (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| CAMILA 0.35 MG TABLET | Generic | $0.15 each |
| errin (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| ERRIN 0.35 MG TABLET | Generic | $0.15 each |
| jencycla (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| JENCYCLA 0.35 MG TABLET | Generic | $0.15 each |
| slynd (on 8/17/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| SLYND 4 MG TABLET | $6.63 each | |