How Long Levonorgestrel Side Effects Usually Last – And When To Seek Support in London
Taking levonorgestrel, commonly known as the morning after pill, can bring a wave of unfamiliar physical symptoms. For many people, the experience raises understandable questions: is this normal, how long will it last, and when should I be concerned? Understanding what to expect makes the days following emergency contraception considerably less worrying.
At Junction Pharmacy, our team in London is here to support you before, during, and after taking emergency contraception. If you have questions or need guidance following a recent dose, do not hesitate to reach out to us directly.
What Is Levonorgestrel And How Does It Work?
Levonorgestrel is a synthetic progestogen used in emergency contraception. It works primarily by delaying or inhibiting ovulation, which prevents fertilisation from occurring. It does not end an established pregnancy. Levonorgestrel is most effective when taken as soon as possible after unprotected sex, and can be used up to 72 hours afterwards, though effectiveness decreases with time. Because it delivers a relatively high dose of hormone in a single tablet, short-term side effects are common and expected.
Common Side Effects And How Long They Typically Last
Most side effects from levonorgestrel are mild, resolve on their own within a few days, and do not require medical treatment. The table below summarises what patients most commonly experience and the typical duration of each symptom:
| Side Effect | How Common | Typical Duration |
|---|---|---|
| Nausea | Very common | Up to 24 to 48 hours |
| Headache | Common | 24 to 48 hours |
| Fatigue or dizziness | Common | 24 to 48 hours |
| Breast tenderness | Common | A few days |
| Abdominal cramps or discomfort | Common | 24 to 72 hours |
| Irregular bleeding or spotting | Very common | A few days; next period may be early or late |
| Vomiting | Less common | Within 2 hours of taking the pill (seek advice if this occurs) |
What To Expect With Your Next Period
One of the most common concerns after taking levonorgestrel is a change to the next menstrual cycle. This is entirely normal and does not mean the medication has not worked. Here is what patients commonly experience:
➤ Your next period may arrive up to a week earlier or later than expected
➤ Bleeding may be heavier, lighter, or last longer than usual
➤ Spotting or light bleeding in the days following the pill is common and not a cause for concern
➤ If your period is more than seven days late, take a pregnancy test to rule out pregnancy
➤ Cycle irregularity typically resolves after one or two cycles
If You Vomit Within Two Hours Of Taking Levonorgestrel
Vomiting within two hours of taking the tablet means the medication may not have been fully absorbed. In this situation, you should contact a pharmacy or clinician as soon as possible to discuss whether a repeat dose is appropriate. Do not simply take another tablet without seeking guidance first. Our team at Junction Pharmacy in Brixton is happy to advise quickly and without judgement.
When To Seek Support After Taking The Morning After Pill
Most people recover from any side effects within a few days and do not need to contact a clinician. However, there are certain situations where seeking support promptly is the right thing to do:
➤ You vomited or had severe diarrhoea within two hours of taking the tablet
➤ You are experiencing severe or worsening lower abdominal pain, which can in rare cases indicate an ectopic pregnancy
➤ Your next period is more than seven days late and a pregnancy test has not been done
➤ You have taken levonorgestrel and are concerned it may have interacted with other medication you are taking
➤ You need advice on longer-term contraception going forward
If you are based in London and have any of the concerns above, our pharmacy team can provide confidential, non-judgemental support.
Frequently Asked Questions
How long do levonorgestrel side effects last?
Most side effects such as nausea, headache, fatigue, and cramping resolve within 24 to 72 hours. Breast tenderness may last a few days longer. Changes to your next period, including earlier or later bleeding or altered flow, can persist for one to two cycles before things return to normal.
Is bleeding after taking the morning after pill normal?
Yes. Light spotting or irregular bleeding in the days following levonorgestrel is common and is caused by the hormonal shift from the tablet. It does not mean the pill has not worked. If bleeding is heavy, prolonged, or accompanied by severe pain, seek advice from a clinician.
Will levonorgestrel affect my regular contraception?
Levonorgestrel does not replace your regular contraception. If you are on the pill, you should continue taking it as normal after taking emergency contraception, but you may need to use additional barrier contraception for a period afterwards. Speak to your pharmacist for personalised advice based on the contraception you use.
Can I take levonorgestrel more than once?
Yes, but it is not intended as a regular form of contraception. It is less reliable than ongoing methods such as the pill, implant, or coil, and repeated use increases the frequency of hormonal side effects and cycle disruption. If you find yourself needing emergency contraception regularly, speak to a clinician about a more effective long-term option.
When should I take a pregnancy test after levonorgestrel?
If your next period does not arrive within seven days of when it was expected, take a pregnancy test. Most home pregnancy tests are reliable from around three weeks after unprotected sex. If you are unsure about timing or need support, our team in London can advise you.
We Are Here When You Need Us
Taking emergency contraception can feel stressful, and questions about side effects or what happens next are completely normal. At Junction Pharmacy in London, we offer confidential, supportive advice with no judgement attached. Whether you need reassurance about symptoms, guidance on your next steps, or information about longer-term contraceptive options, our team is ready to help.
Call us on 02072747599, email junctionpharmacy@gmail.com, or send us a message online. We are happy to talk through your situation and point you in the right direction.
Disclaimer: This article is intended for general guidance and educational purposes only. It does not constitute medical advice and should not replace personalised guidance from your pharmacist or prescribing clinician. If you are experiencing severe symptoms or are concerned about your health following emergency contraception, please seek professional advice promptly.
