Sidena tablets 50mg 4s

4 UNI | €5.00 per 1UNI

Helps you get and keep an erection.
See details below, always read the label

Suitable for:

Men aged 18 years and older with erectile dysfunction.

Active ingredients:



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This Medicine is sold by Boots Retail (Ireland) Limited at the professional discretion of a Boots pharmacist.


Unfortunately, collect from store is unavailable for this product.

Please note that you must be in to sign for this delivery.

We need to ensure that this medicine is suitable for the person it is intended for. Therefore a Boots pharmacist may be required to contact you by email or phone to find out some additional information. If they are unable to speak to you when required your order may be delayed or the pharmacy medicine part of your order may be cancelled.


Please ensure your contact details are correct before ordering this medicine.


Sidena contains the active substance sildenafil which belongs to a group of medicines called phosphodiesterase type 5 (PDE5) inhibitors. It works by helping to relax the blood vessels in your penis, allowing blood to flow into your penis when you get sexually excited. Sidena will only help you to get an erection if you are sexually stimulated. Sidena is a treatment for adult men with erectile dysfunction.

Erectile dysfunction, also known as impotence, is an inability to achieve or maintain an erection that is firm enough to have sex. Erections depend on many different factors, including proper blood flow to the penis. Reduced blood flow to the penis may cause erectile dysfunction. Erectile dysfunction can affect men differently. Some cannot achieve an erection. Others may achieve an erection, but not firm enough for having sex or they may lose the erection before or during sex.

Suitable for

Men aged 18 years and older with erectile dysfunction.


Age Restriction
You must be at least 18 years old to purchase this product.

How to use

Please read the enclosed leaflet carefully before use.
Patient Information Leaflets are updated periodically by the manufacturer.



Always take this medicine exactly as described in this leaflet or as your pharmacist or doctor have told you. Check with your pharmacist or doctor if you are not sure.

•Take 1 tablet, as needed, approximately 1 hour before sexual activity.

•Swallow the tablet whole with water.

•Do not take more than 1 tablet a day.

Sidena will only help you achieve an erection if you are sexually aroused. You and your partner should engage in foreplay just as you would if you were not taking a medicine for erectile dysfunction. The amount of time this medicine takes to work varies from person to person, but it normally takes between 30 to 60 minutes. You may take it up to 4 hours before sexual activity.

Relax and be patient if Sidena does not help you the first time. You can try again later but remember you can only take 1 tablet a day. For most men, Sidena will work the first or second time they try it. If it has been some time since you were able to get or keep an erection, it may take a couple of attempts before you achieve the desired effect. Talk to your doctor if you have tried Sidena and are still not able to get and keep an erection.

If you feel the effect of Sidena is too strong, talk to your pharmacist or doctor.

Do not take Sidena tablets in combination with sildenafil containing orodispersible medicines.

Sidena 50 mg
The tablet can be divided into four equal doses. You have to take at least two quarters (corresponding to 25 mg) to reach the minimum effective dose.

Dividing the tablets

Place the tablet on a hard, flat surface with the scoreline facing upwards. Press with your thumb on the middle of the tablet and the tablet breaks into four equal doses.

If you take more Sidena than you should

If you take more tablets than recommended, contact your pharmacist or doctor immediately. Taking more than the recommended dose may result in side effects and/or more severe side effects. You may experience an increase in side effects and their severity. Doses above 100 mg do not increase the efficacy.

If you have any further questions on the use of this medicine, ask your doctor, pharmacist or nurse.


Warning - Do not exceed stated dose

Hazards and Cautions

Consult your doctor or pharmacist if you are taking, have recently taken or might take any other medicines, complementary therapies or if you have a medical condition. This medicine may not be suitable for you if you have a medical condition or are taking any medications such as those listed in the Patient Information Leaflet. Please refer to the Patient Information Leaflet for further warnings, precautions, side effects and instructions for use for this product.

Do not take Sidena if you:

  • Do not have an erection problem
  • Take any nitrate medicine for chest pain or heart failure
  • Take amyl nitrite, so called "poppers" as recreational drugs
  • Take riociguat (or other guanylate cyclase stimulators) for high blood pressure in the lungs
  • Take ritonavir for the treatment of HIV
  • Have been advised by your doctor to avoid sexual activity because of a problem with your heart or blood vessels
  • Have a severe heart problem such as a recent heart attack or stroke (within the last 6 months), unstable angina (chest pain) or severe cardiac failure (reduced pumping capacity of the heart)
  • Have a severe liver problem
  • Have low blood pressure (below 90/50 mmHg) which can cause symptoms such as tiredness, dizziness, light-headedness, feeling sick, clammy skin, depression, loss of consciousness, or blurry vision
  • Have ever had severe vision loss because of nerve damage in the eyes, such as non-arteritic anterior ischaemic optic neuropathy (NAION); or have a rare inherited eye disease, such as retinitis pigmentosa
  • Have a deformed penis
  • Are a woman
  • Are under 18 years of age
  • Are allergic to sildenafil or any of the other ingredients of this medicine (listed in Patient Information Leaflet)


Consult your doctor or pharmacist if symptoms persist or get worse at any stage.

Keep all medicines out of the sight and reach of children

Active ingredients



Calcium hydrogen phosphate anhydrous, microcrystalline cellulose, copovidone, croscarmellose sodium, magnesium stearate, saccharin sodium, indigo carmine aluminium lake (E132). more less

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