What tadalafil is for
Tadalafil is mainly used to treat erection problems (erectile dysfunction).
It's also sometimes used to treat:
- problems peeing, caused by an enlarged prostate (benign prostate enlargement)
- high blood pressure in the blood vessels that go to your lungs (pulmonary arterial hypertension)
How to take tadalafil
Tadalafil comes as tablets that you swallow.
How much you take and how you take it depends on what you're taking it for.
Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or have any problems taking it.
Some people with erection problems may be told to take 1 tablet 30 minutes before sex. Do not take more than 1 tablet a day as the effects can last up to 36 hours.
Otherwise you usually take 1 tablet at the same time every day. Swallow the tablet whole with some water.
Important
Tadalafil is not usually prescribed together with nitrates. Ask a pharmacist or doctor for advice if you take nitrates such as glyceryl trinitrate (GTN) for chest pain.
If you buy tadalafil without a prescription, you're advised to have a check-up with your doctor within 6 months of starting on it. Erection problems can be a sign of other serious health conditions, such as diabetes or heart problems.
If you miss a dose of tadalafil
If you take tadalafil daily and forget to take a dose, take it as soon as you remember, unless it's nearly time for your next dose.
If it's nearly time for your next dose, skip the missed dose and take the next one at the usual time.
Do not take 2 doses to make up for a forgotten one. Do not take more than 1 dose a day.
If you take too much tadalafil
Taking an extra dose of tadalafil can be dangerous.
Urgent advice: Get help from NHS 111 if:
- you've taken more than your prescribed dose of tadalafil
You can call 111 or get help from 111 online.
If you're told to go to A&E, do not drive. Ask someone to drive you or call 999 and ask for an ambulance.
Bring the tadalafil packet or leaflet inside it, any remaining medicine, and any other medicines you take.
Side effects of tadalafil
Like all medicines, tadalafil can cause side effects, although not everyone gets them.
Common side effects
Common side effects of tadalafil include:
- indigestion
- muscle aches, and arm and leg pain
- back pain
- blocked or stuffy nose
- flushed face
- headache
Tadalafil will not usually affect your ability to drive, ride a bike or use machinery, but some people report feeling dizzy. If you feel dizzy after taking it, wait until the dizziness stops.
Non-urgent advice: Speak to a pharmacist or doctor if:
- you have any side effects that bother you or do not go away
They may be able to give you advice about how to reduce any side effects.
Find a pharmacySerious side effects
Tadalafil can sometimes cause serious side effects, although most of them are rare.
Possible serious side effects of tadalafil include:
- an allergic reaction (anaphylaxis) – causing symptoms such as a swollen throat or tongue, a raised, itchy rash and difficulty breathing
- sudden problems with your hearing or eyesight
- noticeable heart beats (palpitations)
- difficulty breathing or shortness of breath
- prolonged or painful erection (priapism)
- seizures (fits)
- chest pain
Urgent advice: Call NHS 111 if:
- you're taking tadalafil and think you might be having serious side effects
More about side effects
These are not all the side effects of tadalafil.
For a full list, see the leaflet that came with your medicine or search for your medicine leaflet on the electronic medicines compendium website.
You can report any side effects you get on the Yellow Card website
Who can and cannot take tadalafil
Most adults can take tadalafil, but it's not suitable for everyone.
For example, it may not be suitable if:
- you've had an allergic reaction or serious side effect from tadalafil before
- you've recently had a heart attack or stroke
- you have low blood pressure or uncontrolled high blood pressure
- you have liver or kidney problems
- you have blood cancer (leukaemia) or cancer of the bone marrow (multiple myeloma)
- you have sickle cell anaemia
- you've ever had vision loss in one eye caused by reduced blood flow to the optic nerve (non-arteritic anterior ischemic optic neuropathy)
- you have a curved or bent penis, which makes getting an erection painful or difficult
Before taking tadalafil, tell your doctor or pharmacist if you have any medical conditions.
Pregnancy, breastfeeding and tadalafil
You're advised to avoid taking tadalafil when you're pregnant or breastfeeding.
Tell your doctor if you're breastfeeding, pregnant or you get pregnant while taking tadalafil.
Taking tadalafil with other medicines, food and drink
There are also some medicines, herbal remedies and supplements that may not mix well with tadalafil.
This includes some types of:
- heart medicines, such as nitrates for chest pain (angina)
- epilepsy medicine (anticonvulsants)
- medicine for pulmonary hypertension or high blood pressure
- antibiotics, including rifampicin, erythromycin and clarithromycin
- medicine for enlarged prostate or erectile dysfunction
- medicine for HIV or AIDS
- antifungal medicines
Before taking tadalafil, tell your doctor or pharmacist if you're taking any other medicines, herbal remedies, vitamins or supplements.
Taking tadalafil together with poppers (amyl nitrate) or illegal drugs, such as amphetamines, ecstasy and cocaine, can increase the risk of serious side effects.
Food, drink and alcohol with tadalafil
Do not drink grapefruit juice while taking tadalafil.
Drinking alcohol while taking tadalafil can increase your risk of low blood pressure, which can make you feel dizzy or light-headed.
It's also best to avoid drinking too much alcohol as this can make getting an erection more difficult.
Find out more about your medicine
To find out more about your medicine, you can:
- check the leaflet that comes with it
- search for your medicine leaflet on the electronic medicines compendium website
- speak to a pharmacist or doctor for advice