Side Effects of ellaOne: What to Expect After Taking It

ellaOne’s active ingredient, ulipristal acetate, works by delaying or preventing the release of an egg from the ovaries (ovulation). It does this by binding to progesterone receptors to stop the hormone from attaching to its receptors, which causes ovulation.

ellaOne is most effective if it is taken before ovulation happens, as it cannot prevent pregnancy if an egg has already been released. One of the advantages of ellaOne is that it can be taken up to 5 days after unprotected sex has occurred, compared to other morning after pills that contain levonorgestrel, such as Levonelle, which only remain effective for up to 3 days.

Research shows that ellaOne is 98% effective if it is taken up to 120 hours after unprotected sex.

Any medication has the potential to cause side effects, including ellaOne. These side effects can be split into common, uncommon, and rare, depending on how many people get them.

The most common ellaOne side effects, affecting up to 10% of people, are:

• feeling sick (nausea)
• stomach pain or discomfort
• being sick
• painful periods
• pelvic pain
• breast tenderness
• headache
• dizziness
• mood swings

You may notice that your next period after taking ellaOne is lighter, heavier, earlier, or later than usual.

Some of the less common side effects, affecting up to 1 in 100 people, include:

• unusual or irregular vaginal bleeding
• appetite changes
• mood changes
• acne
• sleep changes

Rarely, in 1 in 1,000 people, ellaOne can cause:

• genital pain or itching
• loss of concentration
• fainting
• thirst
• unusual sensations in the eye
• taste changes

Although these side effects can be unpleasant or uncomfortable, they usually only last a short while and are not usually a cause for concern.

You can find a full list of ellaOne side effects in the patient information leaflet.

The only way to know if ellaOne has worked is when your next period arrives. Experiencing side effects is not a sign that it has worked, especially as many of these side effects are also similar to signs of pregnancy.

Side effects are caused by your body interacting with the medication, and not a sign that it is working or not working.

If your next period after taking the morning after pill is unusually heavy or light, is more than 7 days late, or you are experiencing symptoms, such as breast tenderness, feeling or being sick, or stomach pain, you could be pregnant. In this case, you should take a pregnancy test.

If you get side effects from taking ellaOne, they typically last only a few hours to a few days and are usually mild.

However, if you vomit within 3 hours of taking ellaOne, it will not be effective, and you will need to take another pill.

If side effects last for more than a few days, you should contact your doctor for more advice or consider taking a pregnancy test.

Yes, ellaOne can affect your period after you take it by making it come earlier or later, or by changing how heavy it is or how long it lasts. The active ingredient, ulipristal acetate, temporarily affects the hormonal balance that regulates your menstrual cycle by delaying ovulation.

The hormonal changes caused by ellaOne can affect your cycle and next period, but it should return to normal the following month.

Most ellaOne side effects are mild and temporary and can be managed at home. The most common side effects are feeling or being sick. If you vomit within 3 hours of taking ellaOne, you should contact your doctor or pharmacist because you will need to take another dose.

You can manage feeling or being sick by:

• eating smaller, more frequent meals
• avoiding spicy, greasy, or fatty foods
• taking regular sips of water or ginger, peppermint, or camomile tea
• not lying down after you have eaten
• getting fresh air and going for a gentle walk outside

If you are experiencing headaches, you can try:

• getting rest until it passes
• reducing your screen time or using blue light-blocking glasses
• taking frequent sips of water to avoid dehydration
• taking over-the-counter painkillers, such as paracetamol or ibuprofen

If you get stomach cramps, you can help relieve them by:

• getting plenty of rest
• holding a warm compress or heat pad over your stomach
• taking over-the-counter painkillers
• trying gentle exercise, like yoga or walking
• staying hydrated
• prioritising good quality sleep

If you find any side effects difficult to manage or are concerned, contact your doctor or pharmacist for more advice.