Norgestimate

Norgestimate is a third-generation synthetic progestin used exclusively in the Combined Pill along with Ethinyl Estradiol, a synthetic oestrogen. While it’s rarely seen without its partner in crime, it is used alone as a hormone therapy for menopausal women in some countries.  

How does it work?

Norgestimate directly affects the endometrium (the inner layer of the uterus) and inhibits luteinising hormone and stops ovulation¹. 

Progestins in combined contraceptive pills can also make your cervical fluid thicker, stopping sperm from being able to enter your uterus. 

What is it used in?

Combined Pill

• Cilest
• Lizinna

Is it androgenic?

Yes, weakly.

What are the side effects?

As Norgestimate is almost always taken with Ethinyl Estradiol, it’s virtually impossible to say which side effects it alone can be blamed for. The following side effects have been recorded as common or very common when Norgestimate is taken alongside Ethinyl Estradiol 2: 

• Anxiety
• Asthenic conditions (tiredness or weakness)
• Breast abnormalities
• Chest pain
• Constipation
• Depression
• Diarrhoea
• Dizziness
• Gastrointestinal discomfort
• Gastrointestinal disorders
• Increased genital discharge
• Hypersensitivity
• Increased risk of infection
• Insomnia
• Menstrual cycle irregularities
• Altered mood
• Muscle complaints
• Oedema (fluid retention)
• Pain
• Skin reactions
• Vomiting 

References

1. Phillips A, Hahn DW and McGuire JL. Preclinical evaluation of norgestimate, a progestin with minimal androgenic activity. American Journal of Obstetrics and Gynecology. 1992. 167(4 Pt 2):1191-1196. Available from: doi:10.1016/s0002-9378(12)90410-x
2. Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press <https://bnf.nice.org.uk/drug/ethinylestradiol-with-norgestimate.html> [Accessed on 13 August 2020]