In short

  • Cilest side effects are rare, affecting only a small percentage of women who take the pill.
  • 10% of all women taking Cilest experience some period pain, there may also be increased vaginal bleeding.
  • This is a normal response because Cilest can delay your period, making it slightly heavier when it does come.

Cilest side effects are rare, affecting only a small percentage of women who take the pill. 10% of all women taking Cilest experience some period pain, there may also be increased vaginal bleeding. This is a normal response because Cilest can delay your period, making it slightly heavier when it does come. 

Only 1% of women taking Cilest may experience mood swings, depression and anxiety. Swelling of the limbs, loss of appetite and migraines are also possible. 

The rarest side effects are also the most severe. These include difficulty breathing, changes in vision and allergic reactions. If you experience any of these side effects, you should immediately stop taking Cilest and seek medical attention.


View all contraceptive pills

Sources

References

2 sources were selected to match the subject of this article. Link destinations were checked twice when added. This does not mean every statement has been individually source-mapped or clinically approved.

  1. Side effects and risks of the combined pill

    NHS · HTML · NHS contraception safety guidance · Link destination checked 5 September 2026

  2. Combined hormonal contraceptives and venous thromboembolism: review confirms risk is small

    Medicines and Healthcare products Regulatory Agency · HTML · UK regulator drug-safety update · Link destination checked 5 September 2026

Reference links open the cited source pages. If you spot something out of date, tell our content team.

Who wrote this

Written and reviewed by our team

Authored by

Ian Coakley, Content Writer

Content Writer

Ian is Simple Online Pharmacy’s Content Writer; he joined the team in 2021. He has had a varied career path, starting as a science communicator and freelance editor and writer. While Ian has been published in some independent outfits, Simple Online Pharmacy marks his first foray into writing for a corporate entity.

Read Ian’s profile

Medically reviewed by

Karim Nassar, Co-Founder, Pharmacist & Author

Karim Nassar

Co-Founder, Pharmacist & Author

Karim is a registered pharmacist with the General Pharmaceutical Council (GPhC) and was a founding member of Simple Online Healthcare in 2015. With a Master of Pharmacy degree from Strathclyde University, Karim brings a strong foundation in pharmaceutical care and a passion for leveraging digital solutions to improve patient access to healthcare.

Read Karim’s profile

Published

Last medically reviewed

Sources cited

See 2 references

Keep reading

More Contraception advice

View all Contraception advice