Tadalafil

Tadalafil is a medication that is used to treat erectile dysfunction (ED) and pulmonary arterial hypertension. It can help improve the symptoms of ED by increasing the blood flow to the penis, which then makes it easier to get an erection. 

Tadalafil is available as a daily version in 2.5mg and 5mg doses, and an ‘on demand’ version of 10mg or 20mg that is  taken at least 30 minutes before sex.

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Tadalafil works by increasing the blood flow to your penis. It belongs to a group of medications called phosphodiesterase-5 (PDE-5) inhibitors. 

When you take these, the smooth muscle of the penis relaxes. This increases blood flow to the penis, making it easier to both get and keep an erection. One important thing to remember is that you still need to be aroused for these types of medications to work.

Tadalafil works in the same way as Viagra.

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You can get tadalafil through the NHS or buy it online. It’s a prescription-only medication, which means it cannot be bought over the counter and must be prescribed by a doctor. 

You can be prescribed tadalafil from trusted, regulated online services, like Superdrug Online Doctor. 

You’ll need to see your GP if you want to get tadalafil through the NHS.

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There are 4 doses of tadalafil: 2.5mg, 5mg, 10mg and 20mg. 

Tadalafil 10mg and 20mg are ‘on demand’ pills, which are taken at least 30 minutes before sex and can last for up to 36 hours.

• Tadalafil 10mg – this is the standard dose usually prescribed first if you’ve never taken tadalafil or Cialis before. This dose is recommended if you have sex on up to 3 days a week.
• Tadalafil 20mg – you might be able to take this higher dose if the standard dose of tadalafil does not give you the results you’re looking for. But a higher dose increases the risk of side effects.

• Tadalafil 5mg – this is the standard daily dose. If you’ve not taken this medication before, a doctor is likely to prescribe this dose first.
• Tadalafil 2.5mg – this lower daily dose might be best for you if the standard daily 5mg dose gives you side effects. 

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‘On demand’ tadalafil (which comes in 10mg and 20mg doses) lasts up to 36 hours. 

Taking a daily dose of 2.5mg or 5mg means that your ability to get an erection should be improved at all times.

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You should swallow each tablet whole, with water. 

• Tadalafil ‘on demand’ – you should take 1 tablet 30 minutes before you expect to have sex
• Tadalafil daily – you should take 1 tablet once a day, at the same time. You should see results after a few days. To make sure the medication stays in your body at the right level, try not to miss any tablets. 

It’s important to take tadalafil in the way your doctor has told you to, and always read the patient information leaflet that comes with your medication.

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Common side effects of tadalafil include:

• headache
• muscle aches
• back pain
• flushing (redness and a hot feeling) in the face
• blocked nose
• indigestion
• arm and leg pain

 If you get any of the following symptoms, call 111.

• Allergic reactions, including skin rashes
• Chest pain
• Priapism (an erection that is painful and/or lasts more than 2 hours)
• Sudden loss of vision (not being able to see)

Not all men will experience side effects, but it’s a good idea to be aware of what they are, so that you can talk to your doctor if you think you’re having them. Because they have the same active ingredient, tadalafil side effects are the same as the side effects of Cialis.

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You should not take tadalafil if you have:

• heart disease, or have had a recent heart attack or stroke
• abnormal blood pressure 
• unstable angina 
• kidney disease 
• priapism (painful erections lasting over 2 hours)  
• sickle cell anaemia (which will make priapism more likely)
• an unusual penis shape due to scarring
• hearing problems
• liver disease
• fits (seizures)

The following other medications can also affect the way tadalafil works:

• medication for angina (nitrates) 
• alpha-blockers for high blood pressure or prostate issues 
• HIV medication 
• oral anti-fungal drugs
• antibiotics
• other medications for ED
• other medications for pulmonary arterial hypertension 
• stomach acid medication
• epilepsy medication

The following can also change the effect of tadalafil:

• Eating grapefruit or drinking grapefruit juice can increase the levels of tadalafil in your blood, which then could increase your risk of side effects
• Drinking large amounts of alcohol when taking tadalafil can cause a sudden drop in blood pressure, which can reduce the blood flow to your penis and make it less likely for you to get and keep erections

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Healthline (2020). Tadalafil, Oral Tablet. [online] https://www.healthline.com/health/tadalafil-oral-tablet#other-warnings [accessed December 2019].

NICE (2020). Tadalafil. [online] https://bnf.nice.org.uk/interaction/tadalafil-2.html [accessed December 2019].

Eli Lilly and Company Ltd. (2017). Package Leaflet: Information for the User: Cialis 20 mg Film-Coated Tablets Tadalafil. [online]. Available at: https://www.medicines.org.uk/emc/files/pil.7430.pdf [accessed December 2019].

Eli Lilly and Company Ltd. (2013). New Study Shows Men Taking Cialis® (tadalafil) Tablets Once Daily Returned to Normal Erectile Function after Incomplete Response to As-Needed PDE5 Inhibitor Therapy. [online]. Available at: https://investor.lilly.com/news-releases/news-release-details/new-study-shows-men-taking-cialisr-tadalafil-tablets-once-daily [accessed December 2019].

Drugs.com (2020). User Reviews for Tadalafil [online]. Available at: https://www.drugs.com/comments/tadalafil/ [accessed December 2019].

Rxlist.com (2019). Cialis [online]. Available at: https://www.rxlist.com/script/main/rxlist_view_comments.asp?drug=cialis&questionid=fdb77881_pem [accessed December 2019].

Last reviewed: 26/03/2020 by Dr Simran Deo

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