Tadalafil. Drug and Patient Information. Dosage. Overdose. Generic or Brand Tadalafil. For Professionals and Consumers.

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Tadalafil is used to treat male sexual function problems (impotence or erectile dysfunction) by blocking a certain enzyme (phosphodiesterase-PDE5) in the body. In combination with sexual stimulation, Tadalafil helps blood flow into the penis to achieve and maintain an erection.

Brand name: Cialis

Generic Name: Tadalafil


Tadalafil is not indicated for use in women.

Use of Tadalafil does not protect against sexually transmitted diseases (e.g., HIV, hepatitis B, gonorrhea, syphilis). Practice “safe sex” such as using latex condoms. Consult your doctor or pharmacist for more details.

How To Use Tadalafil

Take Tadalafil by mouth with or without food as directed by your doctor.

There are two ways that Tadalafil may be prescribed and taken. It may be taken as needed, or it may be taken once a day every day. Your doctor will determine which is the best way for you to take Tadalafil. Follow your doctor’s directions exactly.

If used regularly every day, your doctor will prescribe a low dose (usually 2.5 to 5 milligrams per day). When Tadalafil is taken only as needed, the dosing may need to be higher. Never take more of Tadalafil than prescribed because you may experience serious side effects. Your doctor will adjust your dosage based on your response and other medications you may be taking (see also Drug Interactions section). Consult your doctor or pharmacist for more details.

When taken as needed, take Tadalafil at least 30 minutes before sexual activity; or use as directed by your doctor.
Tadalafil’s effect on sexual ability may last up to 36 hours. Therefore, do not take more than once daily as needed.
When taken regularly every day, you may attempt sexual activity at any time between your doses. Do not take more than one dose each day.

Avoid eating grapefruit or drinking grapefruit juice while being treated with Tadalafil unless your doctor instructs you otherwise. Grapefruit juice can increase the amount of certain medications in your bloodstream. Consult your doctor or pharmacist for more details.

Overdose when taking Tadalafil

If an overdose of Tadalafil is suspected, contact your local poison control center or emergency room immediately. US residents can call the US national poison hotline at 1-800-222-1222 . Canadian residents should call their local poison control center directly.

Tadalafil Oral Missed Dose

If you are taking Tadalafil on a regular schedule and you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

Tadalafil Oral Notes

Do not share Tadalafil with others, since they may have a problem that is not effectively treated by Tadalafil, or they may have a condition that is complicated by Tadalafil.

Tadalafil Oral Storage

Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. Brief storage between 59 and 86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.

Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your Tadalafil.

Side Effects When taking Tadalafil

Headache, stomach upset, back pain, muscle pain, nasal stuffiness, flushing, pain in arms or legs, dizziness, or vision changes may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.
Remember that your doctor has prescribed Tadalafil because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using Tadalafil do not have serious side effects.

Rarely, a sudden loss of eyesight in one or both eyes (NAION) may occur. This may or may not be due to Tadalafil. If this serious problem occurs, seek immediate medical attention. You have a slightly greater chance of developing this serious eye problem if you have heart disease, diabetes, high cholesterol, certain eye problems (“crowded disk”), high blood pressure, are over 50 years of age, or if you smoke.

Sexual activity may put extra strain on your heart, especially if you have heart problems.

If you have heart problems or experience any of the following serious side effects during sex, stop and seek immediate medical attention:

severe dizziness fainting chest pain

For males, in the very unlikely event you have a painful or prolonged erection lasting 4 or more hours, stop using Tadalafil and seek immediate medical attention, or permanent problems could occur.

Rarely, Tadalafil may cause sudden hearing problems, or ringing in the ears. Stop taking Tadalafil and tell your doctor immediately if these effects occur.

A serious allergic reaction to Tadalafil is unlikely, but seek immediate medical attention if it occurs.

Symptoms of a serious allergic reaction to Tadalafil include:

rash itching unusual swelling severe dizziness trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

Tadalafil Interactions

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.
See also How To Use section for drug-food interactions.

Tadalafil should not be used with the following medications because very serious (possibly fatal) interactions may occur:

nitrates (e.g., nitroglycerin, isosorbide) nitroprusside (or any “nitric oxide donor” drugs) recreational drugs called “poppers” containing amyl or butyl nitrite

If you are currently using any of these medications, tell your doctor or pharmacist before starting Tadalafil.

Before using Tadalafil, tell your doctor or pharmacist of all prescription and non prescription / herbal products you may use, especially of:

alpha-blocker medication (e.g., doxazosin, prazosin, terazosin) drugs that affect certain liver enzymes (CYP 3A4 substrates, inhibitors and inducers such as cimetidine, rifamycins, St. John’s wort, or certain anti-seizure drugs) high blood pressure medicines other medications for impotence.

If you are taking fosamprenavir, amprenavir, ritonavir, nelfinavir, erythromycin, ketoconazole, or itraconazole (examples of potent inhibitors of CYP 3A4), do not take more than a 10 milligram dose of Tadalafilin a 72 hour period. For more details contact your doctor or pharmacist.

This document does not contain all possible interactions. Therefore, before using Tadalafil, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.