Tadalafil

(Generic Cialis)

Disclaimer: The information provided on this page is not a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns about your health, please talk to a doctor.

What is Tadalafil?

Tadalafil is a PDE5 inhibitor that is most commonly used for erectile dysfunction or ED. Tadalafil is the active ingredient in Cialis. Tadalafil is in the same class of medications as Viagra (Sildenafil), Levitra (Vardenafil), and Stendra (Avanafil). These medications may have slight differences in effect, and your doctor may choose one over the other based on your treatment goals.

What is Generic Cialis?

Tadalafil is the generic form of Cialis. Generic medications are required by the FDA to be bioequivalent to the brand medication, meaning that they act the same way in the body and have the same active ingredients. Generic medications also tend to be less expensive than the brand medications and most medications sold in the U.S. are generic.

How does Tadalafil work?

To get an erection, the body uses chemical signals that tell the vessels to open up and flood blood into the penis when mentally stimulated. Normally, the body then almost as quickly uses an enzyme (PDE-5) to break down those blood flow chemicals, causing blood to leave and the erection to go down. Tadalafil works by blocking the breakdown enzyme (PDE-5), to help maintain the blood flow and erection.

How should I take Tadalafil?

Take the dose directed by your doctor by mouth with some water.You may be able to have sexual activity 30 minutes after taking Tadalafil and up to 36 hours after taking your dose. This extended duration of Tadalafil is why this medication is sometimes referred to as “the weekend pill.” Do not take more than one dose daily. You may take your dose on an empty stomach or with food. Take only the amount of Tadalafil your doctor directed you to take, taking more Tadalafil than directed may cause an increased risk of side effects.

How long does Tadalafil take to work?

Most patients will start having a response from Tadalafil 30 minutes after taking their dose, although full effects may take longer. Tadalafil may make it easier to achieve an erection for up to 36 hours after taking one dose.

How long does Tadalafil last?

In most people, the effects of Tadalafil can last up to 36 hours. Even after the effects of the medication have worn off, the medication is still in your system for up to a day after dosing - so do not take more than one dose daily. If you find your dose lasting 4+ hours, seek medical attention as this is considered priapism and could have damaging effects on the tissues.

What should I tell my doctor before starting Tadalafil?

Before taking Tadalafil make sure your doctor knows about any of the following health conditions: Heart conditions, liver, kidney, eye conditions, bleeding disorders, or penile deformities. Also make sure your doctor knows about all of your current medications, supplements, and any other conditions.

What should I avoid while taking Tadalafil?

Drinking alcohol with Tadalafil can cause side effects including low blood pressure or dizziness. Grapefruit may interact with Tadalafil and lead to unwanted side effects. Avoid the use of grapefruit products. Avoid using any other medicines to treat impotence, such as alprostadil or yohimbine, without first talking to your doctor.

What are the common side effects of Tadalafil?

The common side effects of Tadalafil are: headache, indigestion, back pain, muscle aches, flushing, and a stuffy or runny nose. For a full list of possible side effects see the important safety information below.

What if I overdose Tadalafil?

Taking too much Tadalafil can increase adverse side effects of the medication including severe side effects including extremely low blood pressure or having an erection for longer than 4 hours (priapism). If you have taken more than prescribed by your doctor, or you took the directed amount but you are still having these side effects, seek emergency medical attention.

Important Safety Information for Tadalafil

Contraindications:

• Do not take tadalafil if you are also using a nitrate drug for chest pain or heart problems, including nitroglycerin, isosorbide dinitrate, isosorbide mononitrate, and some recreational drugs such as "poppers". Taking tadalafil with a nitrate medicine can cause a sudden and serious decrease in blood pressure.

• Some medicines can cause unwanted or dangerous effects when used with tadalafil. Tell your doctor about all your current medicines, especially riociguat (Adempas). Do not take tadalafil with riociguat.
• Contact your doctor or seek emergency medical attention if your erection is painful or lasts longer than 4 hours. A prolonged erection (priapism) can damage the penis.

Before taking this medication:

You should not use tadalafil if you are allergic to it, or:

• If you take other medicines to treat pulmonary arterial hypertension, such as riociguat (Adempas).
• If you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking tadalafil with a nitrate medicine can cause a sudden and serious decrease in blood pressure.

To make sure tadalafil is safe for you, tell your doctor if you have ever had:

• Heart problems (chest pain, a heart rhythm disorder, heart attack)
• Pulmonary hypertension
• High or low blood pressure
• Previous stroke
• Blood circulation problems
• Retinitis pigmentosa (an inherited condition of the eye)
• Severe vision problems (including NAION)
• Blindness in one or both eyes
• Bleeding problems
• A stomach ulcer
• Pulmonary veno-occlusive disease (PVOD)
• Liver or kidney disease or require dialysis
• A blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia
• A physical deformity of the penis (such as Peyronie's disease)
• If you have been told you should not have sexual intercourse for health reasons
• If you have ever had an erection lasting 4 hours or longer

Drug Interactions:

• Nitrates: Nitroglycerin, isosorbide dinitrate, isosorbide mononitrate, and some recreational drugs such as "poppers". Taking a nitrate medicine with tadalafil can cause a dangerous decrease in blood pressure.
• Guanylate cyclase stimulators: Adempas® (riociguat)
• Alpha-blockers: Hytrin® (terazosin HCl), Flomax® (tamsulosin HCl), Cardura® (doxazosin mesylate), Minipress® (prazosin HCl), Uroxatral® (alfuzosin HCl), Jalyn® (dutasteride and tamsulosin HCl), or Rapaflo® (silodosin)
• HIV protease inhibitors: ritonavir (Norvir®), indinavir sulfate (Crixivan®), saquinavir (Fortovase® or Invirase®), or atazanavir sulfate (Reyataz®)
• Oral antifungal medicines: ketoconazole (Nizoral®) and itraconazole (Sporanox®)
• Antibiotics: clarithromycin (Biaxin®), telithromycin (Ketek®), or erythromycin
• Other medicines that treat high blood pressure
• Other medicines or treatments for ED
• Cialis and generic Cialis also contain tadalafil, tadalafil is also found in a drug called Adcirca used for pulmonary arterial hypertension (PAH). Do not use tadalafil with Cialis, Adcirca, or with any other PDE5 inhibitor or erectile dysfunction treatment (sildenafil).

Side Effects:

Get emergency medical help if you have signs of an allergic reaction to tadalafil:

• Hives, difficulty breathing, swelling of your face, lips, tongue, or throat.

Stop taking tadalafil and get emergency medical help if you have:

• heart attack symptoms - chest pain or pressure, pain spreading to your jaw or shoulder, nausea, sweating
• vision changes or sudden vision loss
• erection is painful or lasts longer than 4 hours (prolonged erection can damage the penis)
• ringing in your ears, or sudden hearing loss
• irregular heartbeat
• swelling in your hands, ankles, or feet
• shortness of breath
• seizure (convulsions)
• a light-headed feeling, like you might pass out

Common tadalafil side effects may include:

• flushing (warmth, redness, or tingly feeling)
• headache, dizziness
• heartburn, nausea, or upset stomach
• abnormal vision (blurred vision, changes in color vision, vision with a blue tinge)
• runny or stuffy nose, nosebleeds
• Rash
• Nausea
• muscle pain, back pain

Heart attack, irregular heart beat, stroke, and death have occurred rarely in men taking Cialis. The majority of these men had severe cardiac problems before taking Cialis. It is not known if Cialis caused these problems.This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Additional Resources

The following links provide further information of the potential risks and benefits of this medication:

• Official Tadalafil PDR
• FDA Tadalafil Prescribing Information