Tadalafil (Cialis): Uses, How It Works, and Safety
Quick summary: Tadalafil is a medicine used for erectile dysfunction in adults, benign prostatic hyperplasia in adult men, and pulmonary arterial hypertension in adults. It is known by brand names such as Cialis, Adcirca,...
This content is for educational purposes only and does not replace medical advice, diagnosis or treatment from a qualified healthcare professional.
Quick summary: Tadalafil is a medicine used for erectile dysfunction in adults, benign prostatic hyperplasia in adult men, and pulmonary arterial hypertension in adults. It is known by brand names such as Cialis, Adcirca, and Alyq in the United States.
This article gives a clear overview of its uses, how it works, and important safety points to review with the official patient information.
Medical disclaimer: This content is for general information only and does not replace advice from a doctor, pharmacist, or the official medicine leaflet. Do not use this page to diagnose a condition or to change any prescribed treatment.
What is tadalafil?
Tadalafil is an active ingredient used in several prescription medicines. In the United States, it is available under brand names including Cialis, Adcirca, and Alyq.
It is used in adults for different conditions, depending on the product and dose.
What is tadalafil used for?
- Erectile dysfunction in adults.
- Benign prostatic hyperplasia in adult men, including men who also have erectile dysfunction, with the 5 mg dose only.
- Pulmonary arterial hypertension in adults with WHO functional class II and III to improve exercise capacity.
How tadalafil works
Tadalafil is a phosphodiesterase 5 (PDE5) inhibitor. It works by blocking the PDE5 enzyme, which helps preserve cGMP in the corpora cavernosa. This mechanism is associated with its effect in erectile dysfunction.
Its use in pulmonary arterial hypertension is based on its effect on blood vessels and exercise capacity in the approved setting.
How tadalafil is taken
Tadalafil is taken by mouth. It may be taken with or without food.
General administration notes
- For erectile dysfunction, food may delay how quickly it starts to work if taken with a large meal.
- Alcohol may temporarily affect the ability to get an erection.
- For pulmonary arterial hypertension, it is also taken with or without food.
Dosage information at a glance
The exact dose depends on the condition being treated, the product, and individual factors such as kidney or liver function. The table below summarizes the information in the source content.
| Use | Information from the source content |
|---|---|
| Erectile dysfunction | 10 mg at least 30 minutes before expected sexual activity; may be increased to 20 mg if needed. A daily regimen may be used in some patients who expect more frequent use, with 5 mg daily and possible reduction to 2.5 mg depending on tolerability. |
| Benign prostatic hyperplasia | 5 mg daily at the same time. |
| Pulmonary arterial hypertension | 40 mg once daily in adults, with adjustments based on renal or liver function as described in the source content. |
Important: Dose selection and adjustments should be confirmed using the official prescribing information and a healthcare professional’s guidance.
Who should not use tadalafil?
The source content lists several situations where tadalafil is contraindicated or not appropriate. These include:
- Hypersensitivity to tadalafil.
- Use with any form of organic nitrate.
- Recent myocardial infarction, hypotension, unstable angina, certain heart failure situations, uncontrolled arrhythmias, or recent stroke.
- Vision loss due to non-arteritic anterior ischemic optic neuropathy.
- Use with guanylate cyclase stimulators such as riociguat.
If there is any history of cardiovascular disease or eye problems, the official leaflet and a clinician’s advice are especially important.
Warnings and precautions
The source content highlights several precautions. These include liver or kidney impairment, penile anatomical deformity, and a history that may increase the risk of priapism.
It also notes caution in some cardiovascular conditions, venous occlusive lung disease, and retinitis pigmentosa.
Before treatment, the source content also notes that prostate carcinoma should be ruled out.
Other points mentioned in the source content
- Do not combine tadalafil with other PDE5 inhibitors or other erectile dysfunction treatments unless specifically directed by a clinician.
- Use caution with alpha blockers and certain CYP3A4 inhibitors or inducers.
- Avoid excessive alcohol consumption.
- It is not recommended in people under 18 years of age.
Kidney and liver function
The source content includes dose limitations and caution in renal and hepatic impairment.
- Severe renal failure: tadalafil is not recommended for some daily regimens and maximum doses are limited.
- Liver failure: dose limits apply, and severe liver failure requires careful benefit-risk assessment.
- Pulmonary arterial hypertension: severe renal insufficiency is not recommended, and severe hepatic insufficiency is also not recommended.
Because these details can vary by indication and product, the official leaflet should always be checked.
Drug interactions
The source content notes that tadalafil levels may be reduced by certain medicines such as phenobarbital, phenytoin, carbamazepine, and rifampicin.
It also mentions caution with potent CYP3A4 inhibitors such as ketoconazole or ritonavir, and with some blood pressure medicines.
Pregnancy and breastfeeding
The source content states that data in pregnancy are limited and that tadalafil should be avoided during pregnancy.
It also notes that tadalafil may be excreted in milk in animal data, and that it should not be used during breastfeeding.
Driving and using machines
No dedicated studies were found in the source content on driving or machine use. Since dizziness has been reported, people should see how they react before driving or using machinery.
Possible side effects
The source content lists the following adverse reactions and side effects:
- Headache, syncope, migraine.
- Blurred vision.
- Chest pain, palpitations, flushing, hypotension.
- Nasopharyngitis, nasal congestion, sinus congestion, rhinitis.
- Epistaxis.
- Nausea, dyspepsia, abdominal pain or discomfort, vomiting, gastroesophageal reflux.
- Rash.
- Myalgia, back pain, pain or discomfort in the extremities.
- Facial edema, peripheral edema, fatigue.
- Diarrhea in people over 65 years.
Any severe or unexpected reaction should be reviewed promptly by a healthcare professional.
When to seek urgent help
The source content specifically highlights priapism, which is an erection lasting 4 hours or more. This requires urgent medical attention.
It also advises stopping sexual activity and informing a specialist if cardiovascular symptoms appear at the onset of sexual activity.
FAQ about tadalafil
▸ What is tadalafil mainly used for?
According to the source content, tadalafil is used for erectile dysfunction in adults, benign prostatic hyperplasia in adult men, and pulmonary arterial hypertension in adults.
▸ Is tadalafil the same as Cialis?
Cialis is one of the brand names for tadalafil in the United States. The active ingredient is tadalafil.
▸ Can tadalafil be taken with food?
Yes. The source content says tadalafil may be taken with or without food, although a large meal may delay its effect for erectile dysfunction.
▸ What should I check before using tadalafil?
Check the official leaflet and speak with a healthcare professional about heart disease, blood pressure, kidney or liver problems, eye history, and possible drug interactions.
▸ Can tadalafil interact with other medicines?
Yes. The source content mentions interactions with nitrates, riociguat, alpha blockers, some CYP3A4 inhibitors and inducers, and other erectile dysfunction treatments.
Safety reminder: Always verify the exact indication, dose, and interaction warnings in the official medicine leaflet or with a pharmacist or doctor, especially if you have heart, liver, kidney, or eye conditions.
Sources and reference points
This article was rewritten from the provided source content and aligned with official medicine-information style references. For detailed product-specific instructions, consult the FDA medication guide and the relevant prescribing information.
Medical disclaimer
This content is for educational purposes only. It should not be used as a substitute for professional medical advice, diagnosis or treatment. Always ask a doctor, pharmacist or qualified healthcare professional before starting, stopping or changing any medicine.
Sources and verification
The following sources or official references are listed to support verification of the medicine information discussed in this article.
Medicine information can change and may vary depending on country, product formulation, patient history and professional guidance. Always check official medicine information and ask a healthcare professional for personal medical questions.