Updated over a week ago

Tadalafil dos and don’ts

First of all, thank you for choosing Numan. If your prescription request for Tadalafil 10mg or 20mg has been accepted, or if you considering whether this treatment may be suitable for you, we'd like to help you learn how to use it to its best effect, and give you some important information before you start taking it.

Do understand how it works

Tadalafil works by helping to keep the blood vessels in your penis open and relaxed, allowing for increased blood flow. This means that when you are sexually aroused, you can achieve a harder and longer-lasting erection.

If you’re interested in understanding the science behind erections and how tadalafil works in more detail, check out Numan’s Erection Handbook, which has everything you need to know about erections and more.

Don’t take it if...

  • You have had an allergic reaction to tadalafil or any similar medications in the past

  • You have low blood pressure or uncontrolled high blood pressure

  • You are taking medications which contain nitrates (usually for chest pain)

  • You are using amyl nitrites (“poppers”)

  • You have recently had a heart attack or a stroke

  • You have a serious heart or liver condition

  • You have a history of non-arthritic anterior ischaemic optic neuropathy (NAION)

  • You are taking riociguat, a medication used for pulmonary arterial hypertension

Tadalafil may not be suitable for you if you:

  • have a deformity of your penis, such as Peyronie’s disease

  • have a serious liver problem

  • have a serious kidney problem

  • have a heart condition, including left ventricular outflow obstruction

  • have sickle cell anaemia, leukaemia or multiple myeloma

Tadalafil should only be used by men over the age of 18 who have erectile dysfunction. It should not be used with other treatments for erectile dysfunction. If you aren’t sure whether you have any of the conditions listed above, please consult your doctor.

Do take it correctly

Taking tadalafil doesn’t result in an instantaneous erection. Tadalafil starts working 30 minutes after you take it, and the effects last for 36 hours. This means that when you are sexually aroused or stimulated within those 36 hours after you take it, you can expect to have a hard and long-lasting erection.

The recommended starting dose for tadalafil is 10mg/20mg taken once per day, as needed. If you feel the effect of tadalafil is not strong enough, feel free to contact us and we can advise you further.

You should not take more than one dose of tadalafil within 24 hours.

It’s worth noting that tadalafil doesn’t alter libido or sexual desire. It also doesn’t have an effect on your testosterone levels.

Do be aware of the possible side effects

If you experience any of the following serious (but uncommon) side effects, you should stop taking tadalafil and seek urgent medical attention :

  • an allergic reaction - symptoms include rash, swelling of the lips, throat and eyelids, sudden difficulty in breathing or wheezing, dizziness, collapse

  • chest pains - you should not use nitrate-containing medication to treat this

  • a prolonged erection lasting more than four hours, which may be painful. This is a medical emergency and you should visit A&E as soon as possible.

  • sudden loss of vision

Some of the most commonly reported side-effects of tadalafil are:

  • headache

  • back pain

  • muscle aches

  • pain in arms and legs

  • nasal congestion/stuffiness

  • feeling hot or flushed, including facial flushing

  • indigestion

When your tadalafil does arrive (which should be within the next 48 hours), please make sure to read the patient information leaflet enclosed. It contains other important safety information as well as a complete list of possible side effects.

In the meantime, if you’ve found your way to the bottom of this text, you’re probably going to be someone who’s going to be interested in our Erection Handbook, a comprehensive guide to erections, how they can go wrong and more.

In case of an urgent medical problem, please contact NHS 111 via 111.nhs.uk or by calling 111. NHS 111 is available 24 hours a day, 7 days a week.

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