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Note: You must complete a short online consultation so that our doctor can ensure that the treatment is suitable for you. The above pricing should only be used as a reference. The final decision to issue this treatment lies with the prescribing doctor.

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What is Tadalafil (Cialis generic)?

Cialis is a highly effective erectile dysfunction medication trusted by men worldwide. Until recently it was on a patent, meaning that the manufacturer held rights to the ingredients, but the patent has expired so its active ingredient Tadalafil is now available to buy in its own right.

Tadalafil is the generic form of branded Cialis. It's just as effective with the only difference being the price which is lower without the Cialis brand name.

Tadalafil works in the same way as all PDE-5 inhibitors such as Viagra and Spedra, but Cialis and Tadalafil are the longest lasting impotence medications available. It's popular with men who want freedom from pill taking before sex.

Tadalafil releases a medication that inhibits the chemical PDE-5, allowing improved blood flow to the penis and helping it stay there until orgasm. Because it works on a physical level Tadalafil isn't able to treat psychological reasons for impotence, but it is useful to help break free from a cycle of anxiety that prevents sexual performance.

All PDE-5 inhibitors are prescription drugs because they can cause interactions with medical conditions and medications, but it is available in a small dose of 5mg, so is more likely to suit men with health complications such as diabetes, a previous stroke, serious heart conditions, and high blood pressure.

A doctor can prescribe Tadalafil to men with erectile dysfunction and to those with an enlarged prostate, but nitrate users should avoid Tadalafil as it increase nitrate's effect.

It is long lasting nature means Tadalafil is referred to as the weekend pill. It is used and appreciated by men who want freedom from timed love making to enjoy more spontaneity.

How does Tadalafil work?

Tadalafil increases the rate of blood flow to the penis. Lack of sufficient blood flow is one of the main reasons men struggle to get and keep an erection.

PDE-5 inhibitors, medically known as a phosphodiesterase type 5 inhibitors, like Tadalafil can help blood flow issues by increasing the flow of blood to penile chambers during sexual arousal.

To get an erection, the first step is in the mind. Sexual stimulation sends chemical messengers to blood vessels in the penis, which dilate and allow blood to enter the corpora cavernosa chambers. These are usually empty, but when filled with blood they create an erection. The process can go wrong in the mind or the penis as the chain reaction takes place.

The chemical sent to blood vessels after sexual stimulation is called cGMP which temporarily relaxes the vessels. After sex, a chemical known as PDE-5 is released to break down cGMP. Tadalafil is a PDE-5 inhibitor – it prevents PDE-5 breaking down the chemical that creates an erection. Using Tadalafil can give back control over gaining an erection and sustaining it.

Some men worry Tadalafil or other medications will create an erection that is inconvenient and won't dissipate, but Tadalafil will only help you get an erection if you are sexually stimulated. Without stimulation PDE-5 inhibitors have no effect.

How to use Tadalafil?

This is a very simple medication to use. It is a discreet, small, and easy to swallow tablet that should be taken with a glass of water. Don't chew, break or cut the pills as this means some of the ingredients are lost and it won't be as effective. Tadalafil is available in different doses so you shouldn't need to cut your medication.

You should give Tadalafil 30 minutes to work, but it can vary depending on your metabolism. For the majority 30 minutes is sufficient time.

Tadalafil should only be taken once in 24 hours, any more can create unwanted side effects. Your doctor will prescribe the right amount that suits your level of erectile dysfunction and overall health.

Another benefit to Tadalafil, alongside its long-lasting capabilities, is that you are able to eat before, during and after the dose. This is not the case with all PDE-5 inhibitors some of which should be taken on an empty stomach. However, all PDE-5 inhibitors including Tadalafil should be taken without alcohol.

Alcohol reduces the effectiveness of Tadalafil and can cause dizziness. It is best to avoid alcohol, but if you choose to have a drink be cautious when you stand up.

Grapefruit juice has been found to interfere with Tadalafil, reducing its effectiveness. It is best to avoid grapefruit juice when using this medication.

Taking a larger amount of Tadalafil won't make it last longer and you put yourself at risk of side effects. Only take the amount prescribed by your doctor in one 24 hour period. If you accidently take too many pills, speak to your doctor.

What dosages are available for Tadalafil?

Tadalafil is available in 5, 10 and 20mg doses. This is a single dose tablet. Your prescription will tell you how much to take as it depends on your level of health, current medications and how much difficulty you are experiencing with ED.

Men taking Tadalafil for an enlarged prostate are usually prescribed a daily low dose of 5mg. Men experiencing impotence problems usually start on a 10 mg dose, and can increase this to 20mg if they still have erection problems. If it creates side effects the dose can be lowered to 5mg. Changing the dosage should only be done under the direction of a doctor.

All PDE-5 inhibitors have slightly different ingredients so if you are experiencing side effects with Viagra or Spedra for example Tadalafil may suit you better. They all work in the same way, but some are simply a better fit with your circumstances and biology.

What are the side effects of Tadalafil (generic Cialis)?

Tadalafil is a generally well-tolerated drug, but it is a prescription drug and therefore may cause some side effects.

If you experience side effects they are likely to be mild and quick lived, but if they don't pass and you find them unbearable speak to your doctor who may be able to change the dosage or prescribe another impotence medication.

Common mild side effects include

  • headaches,
  • nasal congestion,
  • facial flushing,
  • indigestion.

These common side effects often pass as your body gets used to the drug, and men often find it's worth waiting as the results of Tadalafil outweigh mild discomfort.

Less common side effects experienced by few men include

  • chest pains,
  • dizziness,
  • palpitations,
  • a rash,
  • blurred vision.

They are unlikely to affect you, but if you do experience these symptoms stop taking Tadalafil and speak to your doctor.

On rare occasions an allergic reaction is experienced. It's very rare but needs immediate medical help. Symptoms of an allergic reaction are difficulty breathing, hives and a swollen mouth or tongue. Other rare but serious side effects include a sudden loss of vision and priapism – a prolonged, painful erection.

The potential for side effects means you should only take your prescribed amount and never give Tadalafil to anyone else. Keep it locked away from children as it is only suitable for men over 18.

What are the precautions/interactions of Tadalafil?

Because this is a prescription medication there are some precautions and interactions you need to be aware of. Your prescribing doctor will decide if Tadalafil will suit your medical conditions and current medication, so always tell your doctor if you have health problems.

Medical conditions such as high blood pressure, a recent stroke, heart disease, diabetes and other serious conditions means you are unlikely to suit Tadalafil. Men taking nitrates should not use PDE-5 inhibitors because the combination causes nitrate to have a more severe effect. Nitrates are found in some angina drugs and in the recreational drug known as poppers.

There are currently no drugs available to support sexual arousal in women. Tadalafil is a PDE-5 inhibitor that works by widening blood vessels to the penis. It has no effect on women and should not be taken. Women who take Tadalafil will not experience an increased libido but may experience side effects.

How can I buy Tadalafil online on 121doc?

Buying Tadalafil to treat erectile dysfunction is convenient and cuts down on embarrassment and waiting times at your doctor's surgery. Registered UK pharmacies can sell genuine erectile dysfunction medications.

Is Tadalafil available without a prescription?

Tadalafil is a prescription drug due to its potential interaction with other medications and effect on medical conditions. It is not available without a prescription. If you are offered PDE-5 inhibitors off prescription you put your health in danger as the medication may be counterfeit.

Can I buy Tadalafil safely online?

You can buy Tadalafil safely from us with a prescription. We only dispense genuine medication from our registered UK pharmacy.

How do I know it's genuine medication?

If you do not have a prescription you will need a consultation with our doctor. Following this, any prescription for Tadalafil is sent directly from our UK registered pharmacy. Your medication will arrive in its original packaging with a full patient information leaflet.

We are registered with the Medicines and Healthcare Products Regulatory Agency (MHRA). If you have any worries or queries call our customer service line.


Overview Weekend pillGeneric alternative to Viagra
  Active ingredient(s)
Active ingredient(s) TadalafilSildenafil
  Works in
Works in 30-60 min30-60 min
Lasts 36 hours4 hours
Features Long-lastingFast-acting
  Side effects
Side effects Usually mildUsually mild
Alcohol CautionCaution
  How to take
How to take 1 pill max a day1 pill max a day
Price £54.99£29.99
View treatmentView treatment

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Select a condition here or use the top menu. For every condition, we provide you with information as well as the treatments we currently offer. If you don’t know which is best for you, just click the 'Advise-me' button.


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Every order starts with an online consultation. We will ask you medical questions to make sure only treatment that is safe and effective is prescribed. We take into account your lifestyle, health and any other medications you’re currently using.

The consultation is completely free, and takes between 5 and 10 minutes of your time.

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If you need any guidance, you can call, message or email our customer service team via the ‘How can we help you?' section here.

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As soon as you place the order, one of our doctors will review your consultation. On working days, this usually takes around one hour.


If the doctor has any additional questions, you will receive a phone call and an email. We understand you might be at work or busy. Our customer service representatives are always discreet and can call back at a more convenient time if necessary.

Our emails never contain any personal or medical information, only a link to your private account on our website (where you will find your messages).


Once our pharmacy receives your prescription, you will get a second email with your package tracking code.

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All orders include next-day delivery. Alternatively, you can select a delivery date that suits you better.


We also provide a free UPS Access Point service. Pick up your package from one of many collection points across the UK.

With your tracking code, you will know the estimated delivery time. All we need is your signature (or a friend‘s or relative’s).


All parcels are plainly labelled; there is no logo or any indication of its contents. Inside, you will find your treatment as well as a patient leaflet in your chosen language.

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With 121doc’s Subscribe & Save service, you can automatically receive your treatment every few weeks or months.

The order will be generated by us, using the information you provided (including delivery frequency). You don’t have to do anything. Payment is taken two days before shipping.


There are two ways to subscribe. The first is during the order process. The second is via your profile here.

You can cancel or amend your repeat prescriptions at any time.


There are no sign-up fees with this service. Plus, you get a 10% discount off all future prescriptions, increasing to 15% after six orders!

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