Everything you need to know about the morning after pill

We all know the feeling – well, half the population anyway – of the morning after, waking up in someone else's bed and frantically trying to remember if you took your pill yesterday. Or worse, trying to remember if you used a condom.

Luckily you don't have to go searching for information because it's all here, ready for you to peruse and make informed choices about your sexual health.

Firstly, there's two types of morning after pill which carry out their jobs in slightly different ways.

One morning after pill, Levonelle, uses a compound called levonorgestrel, a synthetic copy of the hormone progesterone, which delays the release of an egg.

It can be taken up to 72 hours (three days) after having unprotected sex and is 95 per cent effective if taken within 24 hours. After 48 hours, however, its effectiveness is reduced to 58 per cent.

However, another form of the morning after pill is EllaOne. EllaOne uses a chemical called ulipristal acetate which inhibits the efficiency of progesterone, also delaying the release of an egg.

It can be taken within 120 hours (five days) of having unprotected sex and is 98 per cent effective.

But it's not just as simple as that. The morning after pill has conditions and side effects that you need to know:

Not everyone can take it

Although the morning after pill is relatively harmless, it can be dangerous for people who suffer from certain conditions. These include: severe asthma, liver damage and certain stomach conditions.

If you have any doubts about if the morning after pill is for you, visit your GP rather than going to the pharmacy and they should advise you.

Certain drug interactions can make it less effective

Be wary, as the effectiveness of the pill can be reduced if you're taking medicine to treat epilepsy, HIV or tuberculosis (TB) or medicines like omeprazole which reduce stomach acidity.

The antibiotics rifampicin or rifabutin and herbal medicines such as St John's Wort can also reduce the effectiveness of the morning after pill.

There can be side effects

Both pills have the same side effects. These include: nausea, stomach pains, headaches, breast pain and dizziness.

You can also experience alterations in your period, such as bleeding between periods or very heavy periods.

There's no limit on how many times you can take it

That's right, no limit. But this obviously doesn't mean we're advising you to start popping morning after pills left right and centre. It should be reserved for emergencies only.

Plus, there are many long term contraceptive methods such as the contraceptive pill, the IUD coil, the implant or the injection which are all much more affordable and effective than the morning after pill.

It doesn't protect you from STIs

Unfortunately, this pill's gonna need to come with a side of sexual health screening. This can be done either by ordering a home testing kit or taking a trip to your local STI clinic.

You can still drink alcohol

A big woop woop for this! Alcohol doesn't interact with either of the morning after pills so don't need to worry about cancelling that night out because you can drink all the alcohol you want – within reason obviously – and still be protected.

Recreational drugs should be avoided, though, as they could interact with the pill and reduce its effectiveness.

You won't be judged

Forget all the horror stories, your doctor or pharmacist will be really chill about it, and you might even get some free condoms!

You can get it for free

Ladies, the days of proving you have a husband and sneaking around back alleys is over. Luckily for us it's the 21st century now and contraception can be found almost as easily as buying a toothbrush.

You can get the morning after pill for free from sexual health or genitourinary medicine (GUM) clinics, NHS walk in centres, certain GP surgeries, most pharmacies (call to check just to be safe) and some A&E units.

Lots of these places will give it to you for free, especially GUM clinics and GP surgeries, but some pharmacies may charge you a small fee. This can be anywhere from £25 to £35.

It won't keep you protected for future liaisons

Don't take the morning after pill as a free pass to go have unprotected sex for the next few days, because it just won't work – and you'll be left wishing you'd looked closer at the leaflet.

It's not the only form of emergency contraception

There's the intra-uterine device (IUD), also known as the coil, which can be fitted within five days of having unprotected sex and protect you from pregnancy.

The IUD is 99 per cent effective and lasts long term for up to 10 years. You can essentially kill two birds with one stone with the coil, making it a really good option.

Now you're informed about the morning after pill, go forth and make safe and sensible sexual decisions. Thank us later.

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• An honest guide to everything about the pill before you start taking it