Morning After Pill Side Effects: What to Expect

When you take the morning after pill, it will prevent ovulation from happening, so even if you had unprotected sex, an egg will not be released and pregnancy cannot occur. Some people get side effects after taking the morning after pill, while others do not get any at all.

All medications can cause side effects, and the morning after pill is no exception. However, it’s important to note that not everyone will get them, and that mild side effects may be preferable compared to the possibility of unwanted pregnancy. The morning after pill side effects can be split into common, less common, and rare.

Common side effects

The most common side effects of the morning after pill, affecting up to 1 in 10 people, include:

• feeling sick (nausea)
• stomach pain or discomfort
• being sick (vomiting)
• painful periods
• pelvic pain
• breast tenderness
• headache
• dizziness
• mood changes
• muscle pain
• back pain
• tiredness

Less common or rare side effects

Less common side effects of the morning after pill, that may affect up to 1 in 100 people, include:

• diarrhoea
• heartburn
• dry mouth
• wind
• unusual or irregular vaginal bleeding
• heavy periods and prolonged PMS
• vaginal irritation or unusual discharge
• changes to your appetite and sex drive
• hot flushes
• anxiety or agitation
• trouble sleeping
• sleepiness
• migraine
• visual disturbances
• acne
• itchy skin

Rare morning after pill side effects include:

• genital pain or itching
• pain during sex
• ruptured ovarian cyst
• unusually light period
• loss of concentration
• vertigo
• shaking
• disorientation
• fainting
• unusual sensation in the eye
• red eye
• light sensitivity
• dry throat
• taste changes
• thirst
• allergic reactions

If you get any serious or severe side effects, speak to a doctor straight away. In an emergency, such as a severe allergic reaction, which can cause difficulty breathing, swelling of the face and throat, and fainting, someone should call 999.

A full list of the potential side effects can be found in the patient information leaflet that comes with the morning after pill you are given.

Most morning after pill side effects are temporary and mild, usually only lasting between 1 and 3 days. If you notice changes to your period, it can take a few menstrual cycles for these to return to normal. However, studies have shown that most of the changes are resolved by the following cycle.

If you get any side effects that concern you or persist for longer than you would expect, speak to your doctor or pharmacist for more advice.

Many of the side effects that the morning after pill can cause are temporary, mild, and can be easily managed at home. The most common side effects are feeling or being sick.

If you are sick within 2 to 3 hours of taking the morning after pill, you will need to take another one because it may not be effective.

Side effects, such as feeling or being sick, or diarrhoea, can be managed by:

• eating smaller, more frequent meals
• avoiding spicy, fried, or greasy foods and caffeinated or alcoholic drinks
• sipping water or ginger tea to help ease the symptoms and prevent dehydration
• getting some fresh air, perhaps by taking a short walk outside
• avoiding lying down after eating

Headaches can be managed by:

• getting some rest
• limiting screen time
• taking over-the-counter painkillers such as paracetamol
• taking frequent sips of water to prevent dehydration

You can manage stomach cramps by:

• resting
• taking over-the-counter painkillers, such as paracetamol or ibuprofen
• holding a hot water bottle or warm compress over your stomach
• doing some gentle exercises, like yoga or walking

If the morning after pill makes you feel tired or fatigued, try:

• getting plenty of rest
• avoiding drinking caffeinated drinks, which may disrupt your sleep patterns
• going to bed at the same time each night and waking at the same time each morning

If you get breast pain or tenderness, you can manage it by:

• wearing a supportive bra
• taking over-the-counter painkillers
• applying a warm compress

If you find any morning after pill side effects too difficult to manage, speak to your doctor for more advice.

The side effects of ellaOne and levonorgestrel (Levonelle) are similar and include headaches, dizziness, feeling or being sick, and stomach pain. Both can also affect your next period, making it heavier, lighter, earlier, or later.

Although their side effects are not significantly different, ellaOne and Levonelle have different windows of effectiveness.

In rare cases, the morning after pill may cause an allergic reaction. Symptoms include:

• difficulty breathing or swallowing
• swelling of the lips, tongue, throat, or face
• itching or hives

If you get any of these symptoms, you should call 999 or get someone to take you to A&E as this is an emergency.

Like any medication, the morning after pill can cause side effects, but they are usually temporary and mild. It can cause changes to your period, but these often resolve and should return to normal within a few cycles.

The morning after pill is intended for emergency use only, such as if you have had unprotected sex or your usual contraception method has failed. If you find you need the morning after pill more regularly, you should consider other contraception types, such as the contraceptive pill.