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What Mercilon is and what is it used for?
Mercilon is a combined contraceptive pill. It contains two types of hormones, oestrogen and progestogen (150 micrograms desogestrel and 20 micrograms ethinylestradiol). It is used to prevent pregnancy and can be useful in the management of heavy/ painful periods, polycystic ovarian syndrome, premenstrual syndrome and acne. Mercilon provides effective reversible contraception if taken correctly and good cycle control.
Mercilon prevents pregnancy by:
- Preventing ovulation (the release of an egg).
- Causing the mucus at the cervix (neck of the womb) to thicken, preventing sperm from entering the womb.
- Thinning the lining of the womb, making it more difficult for a fertilised egg to implant.
Contraceptive pills do not protect against sexually transmitted infections (STIs). You should always use a barrier method such as a condom to reduce your risk of STIs.
Here is some important information on the combined pill.
Important Medical Information
Who is this service suitable for?
This service can provide treatment for female (birth sex) patients who require contraceptive treatment to:
- Prevent pregnancy
- Regulate troublesome periods
- Manage hormonal-related acne
You can apply for this treatment if you are aged between 17 and 49 years. A risk assessment will be carried out to determine if it is safe to prescribe this pill for you.
To use this service safely, we require up to date height & weight measurements and a recent blood pressure reading. If you have had a recent blood pressure check by your GP/ nurse, you can use this. If not, a reading from your local gym, pharmacy or home monitor can be used.
Finding the right pill for you can take a little trial and error. If you are experiencing significant side effects with your current pill, please let us know and we can advise on safe alternative options.
Please be aware, this service is not suitable if you have malabsorption problems from any cause, including after weight loss surgery (e.g. gastric band or sleeve). You should speak with your local GP or family planning clinic for contraceptive advice.
How do you take Mercilon?
- Start it on days 1-5 of your next period and you will have full contraceptive cover immediately.
- If you have not been sexually active since your last period, you can start it at any time of your cycle. If taken correctly, you will have full contraceptive cover after 7 days of pill-taking. You should use additional contraception during this 7 day lead-in time.
- If you are changing from another pill/ form of contraception, please contact us via your patient record for specific instructions.
Each pill packet contains 21 pills which are labelled 1-21. Traditionally, combined contraceptive pills like Mercilon are taken for 21 days with a 7-day break, and this cycle is then repeated. It is important that you take your pill at the same time every day.
There is no medical reason to have a 7 day pill free break. It is now recommended that contraceptive pills can be used in cycles as follows if preferred, to provide more reliable contraceptive cover and better bleeding control:
- 21-day use with a 4-day break (most pill-free intervals should now be 4 days).
- 3 packets together with no break and then a 4-day break.
- Continuous use of the pill until spotting for 2 days, then a 4-day break and then restart the pill and continue until spotting occurs again.
If you follow a set pattern and have a planned break, you will usually bleed during this time. Make sure you start the next pill packet after the recommended pill-free break, regardless of your bleeding pattern.
It is essential that you take your pill around the same time every day.
These are examples of ‘off-licence’ pill prescribing. This means they are being used in a different way to that detailed on the product licence by the drug company. These methods of pill use are supported by the Faculty of Sexual and Reproductive Health. They are considered to be safe.
We can offer you advice on this, just send us a message via your account when you have completed the request questionnaire.
What are the potential side effects of Mercilon?
Occasionally skin changes such as acne, decreased libido (sex drive), altered mood and fatigue are reported.
If you develop any of these symptoms and they are persisting, or you are concerned, please speak with your doctor. There are many alternative pill options to consider.
Combined pills like Mercilon can cause increases in blood pressure. It is not medically safe to take this pill if you have high blood pressure. A blood pressure check should be performed every 6 months to monitor for this as you are unlikely to have any symptoms.
For full details of the potential side effects of these medications, please ensure that you read the patient information leaflet that comes with your medication before you start to use it.
Does taking Mercilon increase my risk of getting a blood clot?
You should see a doctor immediately if you develop any of the following symptoms when taking the combined pill:
- Pain or swelling in the legs.
- Severe chest pain.
- Breathlessness or coughing up blood.
- Bad fainting attack or collapse.
- Unusual headaches or difficulty with speech or sight.
- Numbness or weakness of a limb.
Mercilon has a relatively higher risk profile than some other combined contraceptive pills.
- If a blood clot develops in the leg, it can cause deep vein thrombosis (DVT).
- If it travels to the lung, it can cause a pulmonary embolism (PE).
- If it travels to the heart, it can cause a heart attack.
- If it travels to the brain, it can cause a stroke.
The risk of developing a blood clot is greatest in the months immediately after starting Mercilon, or when restarting after a break of at least one month. This risk reduces over the first year of use and then remains stable. It is for this reason that frequent starting and stopping of Mercilon should be avoided.
Other things that can increase your risk of developing a blood clot when taking Mercilon include:
- Being overweight.
- Increasing age (from 35 years and older).
- Having a family member with a blood clot ages <45 years.
- Postpartum (6-12 weeks post-delivery).
- Reduced mobility (even temporarily).
The more of these risk factors that apply to you, the greater your risk.
Seek additional advice if you are:
- having a procedure or surgery (of any type)
- planning a long haul flight
- planning a holiday to an area of high altitude
- immobilised for a prolonged period of time
Further information about blood clot risk is detailed in the leaflet that comes with your medication. Please read this before you start this pill .
Can I delay my period using the Mercilon pill?
Some people will experience breakthrough bleeding when taking pill packets back to back though.
What happens if I forget to take Mercilon?
Please note, this advice applies to traditional pill-taking (21 pills then 7-day break).
- If your missed pill is less than 12 hours late:
- Take the missed pill as soon as you remember and continue with your pill packet as usual.
- You will have full contraceptive cover and do not need to use additional contraception.
- If your missed pill is more than 12 hours late, or you have missed more than one pill:
- Take the missed pill as soon as you remember and carry on with your pill packet as usual. You may need to take 2 pills together (Do not take more than one missed pill).
- Use additional precautions for the next 7 days.
- If you have more than 7 days left in your pill packet, then take your break as usual.
- If you have less than 7 days remaining in your pill packet, do not take a break and start your next pill packet. If you do not have a bleed at the end of the second packet, you should do a pregnancy test.
- If your missed pill was in the first week of your cycle and you had unprotected sex, then you should speak with a health care professional as you may need emergency contraception.
- If you start your new pill packet more than one day late, you will need to use additional contraceptive protection for 7 days.
- If you have unprotected sex during the 7 days you are not fully covered for contraception, you should speak with a doctor via online video consultation as you may need emergency contraception.
If you have any questions or concerns about this, please speak to a Healthcare Professional.
If you are using Mercilon for reasons other than contraception, then missing a very occasional pill is of no significant consequence.
If you have any vomiting or watery diarrhoea, you must use extra precautions during the illness and for seven days after the illness ends.
Can I take other medications with Mercilon?
Please seek advice from a healthcare professional (e.g. doctor, pharmacist or nurse):
- Before starting any new medications, herbal remedies or supplements if you are taking Mercilon.
- If you are taking regular medication and are planning to start using Mercilon (or any contraceptive)
Examples of some medications that can interact with Mercilon include EllaOne (emergency contraceptive pill), St John’s wort, antiviral medications used to treat HIV/ AIDs, certain epilepsy medications, griseofulvin antifungal, rifampicin antibiotic (please note, other antibiotics do not affect Mercilon).
Contraceptive Pill, Patch & Ring Options That We Prescribe
Too busy to see your GP? Order your repeat prescription for the contraceptive pill, patch or ring online with Webdoctor.ie! Once your request has been approved, we can send your prescription directly to your chosen Irish pharmacy via secure Healthmail. If you do not see your pill listed, please email us for advice.
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We issue prescriptions for generic name medicines to ensure maximum availability of treatments. Please check your dispensed prescription before leaving the Pharmacy as no changes can be made after that point.
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