Cialis

Cialis is a brand name for the generic drug tadalafil, a phosphodiesterase 5 (PDE5) inhibitor. PDE5 inhibitors block the PDE5 enzyme to boost levels of a chemical called nitric oxide. Nitric oxide causes a cascade of chemical reactions promoting relaxation of the blood vessels to enhance blood flow. This improves the ability to gain and maintain an erection in patients with erectile dysfunction (ED).

What You Need To Know About Erectile Dysfunction

Through the same mechanism, Cialis also relaxes the smooth muscles of the urinary bladder and the prostate, helping alleviate some of the symptoms associated with an enlarged prostate in patients with benign prostatic hyperplasia (BPH).

What is Cialis used to treat?

Cialis is approved by the US Food and Drug Administration (FDA) to treat ED and the symptoms of BPH, which usually include difficult, painful, or unusually frequent urination. The drug is particularly useful for treating patients with both conditions.

Dosage forms and strengths

Cialis is available in a single formulation, oral tablets, in the following strengths: 2.5mg, 5mg, 10mg, and 20mg.

How do you take Cialis?

How you take Cialis will depend on the condition you’re treating.

Regardless of whether you’re taking it as needed or every day, you shouldn’t take more than one dose of Cialis daily. The drug boosts sexual performance for up to 36 hours, so there’s no need to take it multiple times per day, even if you plan to engage in sexual activity more than once.

For erectile dysfunction

A higher dose of Cialis is used when treating ED. Doctors usually prescribe 10mg as needed, to be taken before sexual activity. It can also be taken as a 5mg dose once daily, regardless of the timing of sexual activity. The effects of the drug may last as long as 36 hours, so there is no need to take it more than once a day. 

Some people may need an adjustment to lower (5mg) or higher (20mg) doses, depending on their body’s response to the drug. Do not change the prescribed dose without consulting your doctor first.

For benign prostatic hyperplasia

The dose is lower when used for the treatment of BPH. Doctors typically prescribe 5mg taken around the same time each day with or without food.

Some people take Cialis for both conditions. In those cases, doctors usually recommend a scheduled dose of 5mg taken at the same time each day.

Seeing results

Cialis works quickly. After a single dose, the drug reaches peak concentrations in the blood within 30 minutes to six hours.

If you are prescribed Cialis to improve sexual function, take it at least 30 minutes before you plan to engage in sexual activity. An erection does not take place spontaneously after taking your dose. Sexual stimulation is needed to trigger the release of nitric oxide before the effects of this drug can be seen. Cialis stays active in your system for up to 36 hours. 

In the case of BPH, it may take a few daily doses to experience an improvement in the associated symptoms.

Who should not take Cialis?

Cialis is typically well-tolerated. However, the drug is contraindicated for people who:

• Are taking nitrates

• Have a known hypersensitivity to tadalafil or a similar drug

• Have a history of nonarteritic anterior ischemic optic neuropathy (NAION) or other hereditary degenerative retinal disorders (including retinitis pigmentosa)

Additionally, the drug should be prescribed cautiously (or with adjusted dosage) in patients with any of the following conditions:

• Hereditary degenerative retinal conditions

• Multiple myeloma, leukemia, sickle cell anemia, or other conditions that may increase the risk of prolonged erections

• Peyronie disease or any other condition causing irregular penis shape

• Sexual activity is inadvisable for you due to compromised heart health

• Kidney or liver impairment

• Bleeding disorders

• An active stomach ulcer

• Certain heart conditions:

  • Aortic stenosis or other left ventricular outflow obstruction

  • A heart attack within the past 90 days

  • Unstable angina (cardiac chest pain) or angina related to sexual intercourse

  • Heart failure (New York Heart Association Class 2 or higher) within the past six months

  • Uncontrolled arrhythmias

• Stroke in the past six months

• Uncontrolled high or very low blood pressure

• Risk factors for NAION

• Alcohol use disorder or substantial alcohol intake

• Using street drugs containing nitrates or nitrites (such as amyl nitrite “poppers”) 

Potential side effects of Cialis

Cialis has known side effects. Most are mild and resolve without intervention. However, some severe adverse effects require urgent medical attention.

Common side effects of Cialis include the following:

• Nausea

• Heartburn or indigestion

• Diarrhea

• Headache

• Nasal congestion

• Flushing (reddening of the skin)

• Cough

• Pain in the stomach, back, arms, legs, or muscles

• Elevated blood pressure

Additionally, the following severe side effects have been reported:

• Blurred vision

• Sudden decrease or loss of vision

• Changes in color vision

• Sudden decrease or loss of hearing

• Tinnitus (ringing in the ears)

• Dizziness

• Chest pain

• Difficulty breathing or swallowing

• Hives or rash

• Blistering or peeling of skin

• Swelling of the face, eyes, lips, tongue, throat, hands, lower legs, ankles, or feet

• A persistent or painful erection lasting longer than four hours

• Joint pain

• Nosebleeds

In some cases, vision loss caused by Cialis is permanent. Serious side effects are not common, but if you experience any of them, you should stop taking Cialis and seek urgent medical care.

Overdose

You can overdose on Cialis. If you think you may have taken too much Cialis, call the National Poison Control helpline. If you or someone in your care loses consciousness, can’t be awakened, or is struggling to breathe after taking Cialis, call 911 or go to the nearest emergency department.

Allergy information

A serious allergic reaction to Cialis is rare; however, you must stay vigilant in monitoring for signs of a drug allergy, which may include swelling of the tongue, lips, or mouth, difficulty breathing or wheezing, increased heart rate, vomiting, and a severe rash or hives. If you experience allergic symptoms while taking Cialis, seek urgent medical care.

Long-term use of Cialis

There are no adequate studies assuring the safety and efficacy of Cialis when used long-term, but research indicates the drug is well-tolerated when taken as needed over a two-year period. More research is needed in this area.

Cialis and pregnancy

While the drug is not approved for use in women, the US FDA designated Cialis as a pregnancy category B drug. There are no adequate studies in humans to determine risk, but animal studies did not demonstrate harm to the fetus.

Breastfeeding

Tadalafil and its metabolites are transferred to breast milk in high concentrations in animal studies, but its presence in human breast milk is unknown. Cialis has not been approved for use in women or infants.

Missed doses

If you take Cialis daily and forget a dose, take the missed dose as soon as you remember. If it’s almost time for the next dose, skip the missed one and do not take more than one dose in a 24-hour period. Never double your dose or take more than prescribed.

Drug interactions

Cialis is known to interact with:

• Alpha-blockers, such as tamsulosin (FloMax), alfuzosin (Uroxatral), terazosin (Hytrin), and (Cardura)

• Antacids containing magnesium hydroxide/aluminum hydroxide (Milk of Magnesia, Dulcolax, Mylanta)

• Antihypertensive drugs like metoprolol (Lopressor), enalapril (Vasotec), amlodipine (Norvasc), and others

• Anti-seizure medications, such as carbamazepine (Tegretol), cenobamate (Xcopri), and phenobarbital

• Cytochrome P450 inhibitors, including antifungal drugs (ketoconazole), some antibiotics (erythromycin, linezolid), HIV protease inhibitors (ritonavir), and grapefruit

• Cytochrome P450 inducers, such as rifampin and natural supplements, including St. John’s wort

• Drugs for treating pulmonary arterial hypertension, such as riociguat (Adempas), tadalafil (Adcirca), bosentan (Tracleer), and sildenafil (Revatio)

• Nitrates, including isosorbide mononitrate, isosorbide dinitrate, nitroglycerin (Nitrostat), and street drugs called amyl nitrites (“poppers”)

• Vericiguat (Verquvo)

This list of interactions is not exhaustive. Before taking Cialis, inform your doctor of all medications, vitamins, herbs, and supplements you take regularly or occasionally.

Notably, Cialis is among the wide range of medications that may be affected by grapefruit and grapefruit juice. Ask your doctor if it’s safe to consume grapefruit while taking Cialis.

Can I drink alcohol while taking Cialis?

Combining alcohol and Cialis can cause a drastic drop in blood pressure and may increase the risk of orthostatic side effects, such as elevated heart rate, dizziness, and headaches. Speak with your doctor before drinking alcohol while taking Cialis.

What to discuss with your doctor before starting Cialis

Cialis is available by prescription only, so you’ll need to speak with your doctor before you start taking it. At your appointment, you should discuss the following topics:

• If you’re healthy enough for sexual activity (before taking Cialis for ED) and if you’ve ever had chest pain (particularly with sexual activity)

• Any conditions you have (or had in the past) affecting the shape of the penis or a history of prolonged, painful erection (priapism)

• Any other health conditions you have now or had in the past, including cardiovascular (heart and blood vessel), kidney, or liver disease, stomach ulcers, bleeding or blood cell disorders, high or low blood pressure, diabetes, eye problems, and hearing issues

• If you’ve ever had a heart attack or stroke

• Any upcoming surgeries, including dental procedures

• All medications, vitamins, herbs, supplements, or recreational drugs you take

• Any allergic reactions you’ve had to drugs in the past

• If you smoke cigarettes

• If you drink alcohol and how often

If you see more than one doctor, ensure every physician who provides your care knows you’re taking Cialis. If you seek emergency care for any reason, inform your healthcare team of all drugs you’re taking. If you need urgent treatment for a heart incident, your medical team will need to know when you took your last dose of Cialis to ensure they provide safe and effective treatment for your heart problem.

Stopping Cialis

Discontinuing Cialis does not cause withdrawal symptoms, and it is safe to stop taking it at any time. However, your symptoms will likely return when you no longer take the drug.

If you experience any severe side effects, stop taking his medication immediately and seek urgent medical help.

Drug approval history

• 2003: The US FDA approved Cialis for treating ED.

• 2011: Cialis was approved for treating the symptoms of BPH, particularly when ED is also present.

Tips for taking Cialis

The following tips can help you maximize effectiveness and minimize side effects while taking Cialis:

• If you’re taking Cialis as needed for ED, take it at least 30 minutes before engaging in sexual activity. An hour or two ahead of time is best.

• Limit your alcohol consumption when taking Cialis.

• Stop taking Cialis and call your doctor if you experience an erection lasting more than four hours.

• Seek urgent medical care if you experience any issues with your vision or hearing while taking this medication.

• Tell anyone providing medical treatment that you use Cialis. You may need to stop taking it ahead of planned surgical procedures.

• Keep all medications out of the reach of children.

Frequently asked questions

How long does it take for Cialis to work?

Cialis can start working in as little as 30 minutes, but the time varies based on individual factors.

How long does Cialis last?

When taken as needed for ED, the effects of Cialis can last up to 36 hours.