Contraceptive Pill Side Effects

The contraceptive pill (also known simply as ‘the pill’) is one of the most common forms of contraception used by women in Ireland today. Used correctly, it is over 99% effective in preventing pregnancy.

The pill is taken orally, and comes in two types: the combined oral contraceptive pill (COC) and the mini-pill or progesterone-only pill (POP). Combined pills contain synthetic versions of two hormones that are produced naturally by your body, oestrogen and progestogen, whereas the mini-pill only contains progesterone.

It is common for the contraceptive pill to cause some side effects, although these will vary from person to person and will depend on the type of pill you take.

The most common side effects from taking the contraceptive pill include:

• mood swings (anxiety, depression)
• sore or tender breasts
• headaches
• nausea
• putting on weight
• stomach pain

These side effects aren’t dangerous and will usually stop soon after the first few months of treatment. Some women may experience breakthrough bleeding or spotting this should settle within the first few months of starting the pill. In the event that it doesn’t please seek medical attention.

There are some less common side effects from the contraceptive pill that can be more serious. These include:

• vomiting or diarrhoea
• rash or hives
• loss of interest in sex
• migraines
• breast enlargement

If you ever experience any of these side effects, or any of your usual side effects become severe, you should stop taking the pill and seek urgent medical attention.

Common side effects are usually only temporary and should go away within the first few months of beginning to take the contraceptive pill. If your side effects don’t go away after three months, discuss trying a new pill or alternative forms of contraception with your doctor.

Try to find a pill that works for you, and to remember that there is no one ‘perfect’ pill! Many women will try several types before finding one that suits them and has the least disruptive side effects.

Dangerous side effects from the contraceptive pill are rare, but have been recorded. The pill is can raise your blood pressure, and has also been known to slightly increase your risk of getting blood clots (thrombosis) and breast cancer.

Your doctor will check your blood pressure to see if this is or could potentially be an issue, and you should seek urgent medical help if you ever think you might have the signs of a blood clot (sudden pain and swelling of the leg or shortness of breath and chest pain) or breast cancer.

Make sure to discuss your full medical history with your prescribing doctor before starting to take the contraceptive pill as it can interact with some medicines. These include:

certain antibiotics (including rifabutin and rifampicin, used to treat meningitis and tuberculosis)
some epilepsy medicines
some HIV medication
herbal remedy St. John’s Wort

The pill should never be taken if you are pregnant and only the progesterone only pill is suitable if you are breastfeeding. If you think you might be pregnant, take a test to confirm.

The pill won’t work for everyone. Some women find that the side effects they experience as a result of using it negatively outweigh the potential benefits, and will choose to stop taking them. Remember, the pill is just one form of contraception! There are many others to choose from if it doesn’t agree with you.

However, for many women, the pill is the easiest, cheapest and most convenient type of contraception.