Many women who take Mercilon do not experience side effects. For those who do, the side effects can vary from person to person and in severity. Side effects are more common in the first 3 months of taking Mercilon when your body is getting used to the hormonal changes.
If the side effects are not manageable or do not disappear after 3 months, talk to your doctor. as they may suggest trying a different pill.
In very rare cases, a side effect of taking Mercilon is that you can develop a blood clot. The Patient Information Leaflet has information on how to recognise a blood clot. Signs include stabbing chest pain, coughing up blood, shortness of breath, immediate loss of vision, unexplained swelling or tenderness in one or both legs. If you develop these symptoms, you should stop taking Mercilon immediately and seek urgent medical help.
Common side effects (may affect up to 1 in 10 people):
- Weight gain
- Nausea or stomach ache
- Mood changes/low mood
- Tender breasts
Uncommon (may affect up to 1 in 100 people):
- Swollen hands, ankles or feet
- Reduced libido
- Being sick or having diarrhoea
- Rash or hives
- Enlargement of breasts
Rare (may affect up to 1 in 1000 people)
- Changes in secretions from the vagina or breasts
- Eye pain if you wear contact lenses
- Harmful blood clots
- Increased libido
- Weight changes
- Bruise-like swellings to the shins
- Skin condition knowns as erythema multiforme
Can Mercilon help with painful and heavy periods? The contraceptive pill regulates hormones in your body which can help some women treat painful periods.
Does Mercilon make your breasts grow? Some women report an increase in the size of their breasts when taking Mercilon due to the changes caused by the hormones in your body. This usually settles down after the first 3 months.
Does Mercilon increase your risk of blood clots? The risk of developing a blood clot when you are not taking an oral contraceptive pill is 2 in 10,000, whereas when you are taking Mercilon this risk is 9-12 in 10,000 women. This is a relatively low risk overall but factors such as family history, weight, age, whether you plan to spend a long time on a plane and whether you have just given birth can increase them. The risk is also higher in the first year that you start taking Mercilon and it returns to normal within a few weeks of when you stop taking it.
Does the Mercilon help acne? It can. The hormonal changes introduced by taking Mercilon can reduce the production of sebum, which is the oily substance that causes acne.
Can taking Mercilon cause mood swings or make you depressed? Some women report that being on Mercilon caused sudden changes in mood or low mood. The research into this can neither prove nor disprove this link. If you feel this is the case for you, talk to your doctor about changing pills.
Can Mercilon cause changes to your weight? Some women report gaining weight when they take Mercilon but again there is no scientific evidence to prove either way that taking the pill either increases or decreases your weight.
Can Mercilon give you low libido? Some women report that taking the combined pill has an impact on their sex drive due to the changes in hormones in their body. If you are worried that this has happened to you, talk to your GP who may suggest trying a contraceptive pill with different hormones.
Does Mercilon stop periods? You still get periods when you take Mercilon because you have a 7-day break during which you have a withdrawal bleed or period. If you want to delay your period, you can take Mercilon back to back. Talk to your doctor if you do this regularly.
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