Oral medications are a simple and effective way to treat erectile dysfunction (ED). The most common erectile dysfunction pill is Viagra, and the next most common is Cialis. Both medications are phosphodiesterase type 5 (PDE5) inhibitors that work by increasing blood flow to the penis. The major difference is that Cialis lasts longer and can be taken daily, giving you erections on demand. Viagra is always taken a few hours before it’s needed and offers less spontaneity.
Continue reading to learn more about Cialis vs. Viagra, including the side effects of each and the differences between them.
What Is Cialis?
Cialis (tadalafil) is a type of PDE5 inhibitor that the Food and Drug Administration approved in 2003. Like other PDE5 inhibitors, it increases blood flow to the penis.
There are two different ways to take Cialis: as needed or daily. If you take the pill daily, the medication stays in your system constantly. This makes it easier to get an erection anytime you need one. This is a good option for people who frequently have sex and like flexibility and spontaneity in their sex lives.
The other option is to take Cialis at least 30 minutes before starting sexual activity. If you take the pill once, the effects of the pill last for about 36 hours. That means you’ll likely find it easier to get an erection during that time.
Cialis is primarily for treating ED but can also treat an enlarged prostate. In addition, under the brand name Adcirca, tadalafil can also treat pulmonary arterial hypertension.
The common side effects of Cialis include:
- Heartburn and indigestion
- Nausea and diarrhea
- Muscle pain
- Drop in blood pressure
Some side effects of Cialis are an emergency. If you experience these you should speak with your healthcare provider immediately:
- An erection lasting longer than four hours
- Sudden vision changes, including blurred vision
- Sudden hearing changes, including ringing in the ears
- Chest pain
- Hives, rash, or blistering
- Difficulty breathing or swallowing
- Swelling of the face or mouth
What Is Viagra?
Viagra (sildenafil) was the first erectile dysfunction pill the FDA approved, back in 1998. Like Cialis, it’s a PDE5 inhibitor that increases blood flow to the penis. The difference is that the effects of Viagra don’t last very long (only about four to six hours). Viagra is always taken before an anticipated sexual activity.
Viagra can only be taken once every 24 hours. So, even if you take it daily there are times when the medication is not in your system, making it difficult to have an erection. Because of that, Viagra is most often used by people who occasionally have sex. The upside to Viagra is that you only take it when you need it.
Common side effects of Viagra include:
- Sleep troubles
- Numbness, burning or tingling in the arm, hands and feet
- Muscle aches
- Changes to vision, including sensitivity to light, seeing a blue tinge, or losing the ability to tell the difference between blue and green
If you experience other, more serious side effects, you should contact your healthcare provider immediately, including:
- Loss of vision or blurred vision
- Changes to hearing or ringing in the ears
- Dizziness and lightheadedness
- Chest pain
- Shortness of breath
- An erection that lasts longer than four hours or is painful
- Itching or boring while urinating
How ED Drugs Work
PDE5 inhibitors work by blocking the breakdown of a substance known as cyclic guanosine monophosphate (cGMP). This, in turn, leads to more nitric oxide in the body. Nitric oxide is a substance that causes blood vessels to relax. This leads to more blood flow to the penis, leading to stronger erections. Both Cialis and Viagra work in this way.
Cialis vs. Viagra
Choosing the right ED pill can be intimidating. Talk with your healthcare provider about your sex life and desired use. In addition, consider the information below.Both medications are generic now and can be found at discounted rates, making them more accessible to the public than ever before.
Which Works Faster?
Both Cialis and Viagra work quickly. If you’re taking Cialis as needed, you take the pill about 30 minutes before sex. Viagra can be taken as long as four hours or as little as 30 minutes before sex. It works best when taken one hour before sex.
Which Lasts Longer?
Cialis lasts longer. Cialis stays in your system for up to 36 hours and may provide support for erections during that entire time. Viagra generally only stays in your system for four to six hours.
Which Is More Effective?
Cialis and Viagra are equally effective. All PDE5 inhibitors are about 70% effective at helping people have better erections. That means seven out of 10 people who take these drugs as prescribed will have more frequent or longer-lasting erections.
However, eating food, particularly high-fat food, can reduce the effectiveness of Viagra.
The dose of Cialis you need will depend on whether you’re taking it daily or as needed. Daily doses are often between 2.5 and 5 milligrams (mg). The as-needed dose is usually 10 mg but can range from 5–20 mg.
The typical dose of Viagra is 50 mg. However, the dosage can range from 25–100 mg. Your healthcare provider will discuss which dose is right for you.
Because Cialis and Viagra are both PDE5 inhibitors, they have similar side effects and safety concerns. Talk with your healthcare provider about which might be best for you.
Main Differences Between Cialis and Viagra
The main difference between Cialis and Viagra is how long each lasts. Cialis stays in your system for up to 36 hours, and you can take it daily. That means you can have erections whenever you want or need them. It’s also possible to take Cialis as needed, about 30 minutes before sex.
Viagra is always taken as needed, usually about an hour before sex. You can take Viagra daily, but because the medication stays in your system for four to six hours, it will not be effective all day.
Talking to Your Healthcare Provider About ED
Talking to your healthcare provider about ED can be intimidating. However, it’s important to remember that sexual health is part of overall health. In addition, ED is extremely common. Healthcare providers have experience talking about ED and providing treatment options without any judgment or shame.
Cialis and Viagra are both pills for treating erectile dysfunction. They are PDE5 inhibitors that allow for increased blood flow to the penis, leading to more frequent and harder erections. Because they are the same class of medications, they have similar side effects and effectiveness. Cialis can be taken daily, providing constant treatment for ED for people who have sex frequently. There is also the option to take Cialis as needed. Viagra is always taken as needed, usually an hour before having sex.
Frequently Asked Questions
Does Cialis make you harder than Viagra?
There’s no research available on whether Cialis or Viagra will give you harder erections. Because they work in the same mechanisms, they’re likely similar. Both are about 70% effective at treating ED.
How long does it take for Cialis to peak?
Cialis reaches its maximum effectiveness two hours after you take it. However, it stays in your body for up to 36 hours and can be taken every 24 hours, so it can work for you constantly.
Is 20mg of Cialis better than 100mg of Viagra?
Both Cialis and Viagra are effective at these doses. Your healthcare provider can help you determine the right dosage for you.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Urology Care Foundation. Erectile dysfunction (ED).
Emling S. Viagra vs. Cialis: Is one right for you? American Association of Retired Persons (AARP).
MedlinePlus. Tadalafil. National Library of Medicine.
MedlinePlus. Sildenafil. National Library of Medicine.
Phosphodiesterase type 5 (PDE5) inhibitors. In LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. National Institute of Diabetes and Digestive and Kidney Diseases. 2017.
By Kelly Burch
Kelly Burch is has written about health topics for more than a decade. Her writing has appeared in The Washington Post, The Chicago Tribune, and more.
See Our Editorial Process
Meet Our Medical Expert Board
Was this page helpful?
Thanks for your feedback!
What is your feedback?
Which erectile dysfunction drug is best for me? ›
The best treatment for erectile dysfunction (ED) is the one that is best for you. Sildenafil (Viagra) and tadalafil (Cialis) are the most commonly prescribed medications for ED, and they have the longest track record. For occasional use, most people start with sildenafil. For regular use, tadalafil can be a better fit.What is the best ED medicine for seniors? ›
- sildenafil (Viagra)
- tadalafil (Cialis)
- vardenafil (Levitra)
- avanafil (Stendra)
Tadalafil has a longer half-life than sildenafil or vardenafil, and a longer duration of action than sildenafil and vardenafil. Most preference studies have shown tadalafil to be preferred, but there are serious limitations to some of these studies.Is there an ED drug better than Viagra? ›
Cialis has comfortably the longest effectiveness period of any erectile dysfunction drug on the market.What is the new erectile dysfunction medication? ›
Of the PDE5 inhibitors that are on the market today, avanafil -- the active ingredient in Stendra -- is the newest. This medication works rapidly, often in as little as 15 minutes, and has a selective effect within your body that means it's less likely to cause some side effects.What drugs cause a man to not get hard? ›
Which ED medication has the least side effects? According to the Boston University School of Medicine, vardenafil (Levitra) may have the least potential for side effects because it's 10 times more biochemically potent than sildenafil (Viagra) and therefore requires a lower dose to facilitate an erection.What is the new treatment for ED 2022? ›
Stem cell therapy for ED involves the injection of your stem cells into your penis. Both animal studies and phase I studies in humans have had promising results. Research in humans suggests that it could eventually be a safe, effective treatment for ED.When do men stop having erections? ›
About a quarter of men said that erection problems started between age 50 and 59, and 40% said they started between age 60 and 69. Having chronic diseases and other risk factors matter with respect to ED, too.What makes you last longer sildenafil or tadalafil? ›
The 'as required' Tadalafil (generic Cialis) has an advantage over Sildenafil in that it lasts a lot longer – up to 36 hours (compared with 4-5 hours for Sildenafil). Some men prefer this as it allows for more spontaneity.
Is there anything better than tadalafil? ›
Vardenafil (Levitra) is more selective than sildenafil and tadalafil (Cialis) to PDE5, which again means a lower dose is needed with potentially less side effects.Does Cialis Work Better Than tadalafil? ›
Generic Cialis, or Tadalafil, is the same as Cialis in terms of its active ingredient (tadalafil), its effectiveness and side effects. The difference you may see is in the cost, with generic medicines tending to be less expensive.What is the downside to Cialis? ›
The most common side effects with Cialis are: headache, indigestion, back pain, muscle aches, flushing, and stuffy or runny nose. These side effects usually go away after a few hours. Men who get back pain and muscle aches usually get it 12 to 24 hours after taking Cialis.How can I regain erectile strength? ›
- If you smoke, quit. If you have trouble quitting, get help. ...
- Lose excess pounds. Being overweight can cause — or worsen — erectile dysfunction.
- Include physical activity in your daily routine. ...
- Get treatment for alcohol or drug problems. ...
- Work through relationship issues.
Effectiveness of all PDE5 inhibitors is similar; although reported effectiveness of Viagra, at 84% is slightly higher than that of Cialis at 81%. However, more men prefer Cialis because of its longer duration of effect.What is the most effective ED treatment 2022? ›
Sildenafil and tadalafil, the active ingredients in Viagra and Cialis, remain the most reliable treatments for erectile dysfunction.Is there a pill you can take everyday for ED? ›
Tadalafil (Cialis) is one of the most popular erectile dysfunction (ED) drugs. Its major appeal? The drug comes in low-dose versions that can be taken daily. This means you can have sex at any time, rather than needing to take a pill from time to time as needed like other ED brands.What is the fastest way to cure ED? ›
- Lifestyle changes. Adjusting the lifestyle can improve many issues that cause ED, such as diabetes and clogged arteries. ...
- Pelvic floor exercises. ...
- Counseling or couples' therapy. ...
- Herbal and alternative remedies. ...
- Medication. ...
- Medication changes. ...
- Mechanical devices. ...
There are psychosocial factors that contribute to ED, such as stresses at work and home, financial issues, deadlines, moving and depression. There are also medical reasons, such as high blood pressure, high cholesterol, diabetes or low thyroid hormone levels.What is the safest way to treat erectile dysfunction? ›
Oral Drugs (PDE5 inhibitors)
Drugs known as PDE type-5 inhibitors increase penile blood flow. These are the only oral agents approved in the U.S. by the Food and Drug Administration for the treatment of ED. For best results, men with ED take these pills about an hour or two before having sex.
Are there any anxiety medications that don't cause erectile dysfunction? ›
- Bupropion (Wellbutrin XL, Wellbutrin SR)
- Mirtazapine (Remeron)
- Vilazodone (Viibryd)
- Vortioxetine (Trintellix)
Incurable causes of ED
Any problem affecting nerves in the body can also interrupt the nerve messages between the penis and the brain, including: injuries to the spinal cord or brain, Parkinson's disease, Alzheimer's disease, multiple sclerosis, or strokes. There are no cures yet for these conditions.
If ED is caused by a lifestyle factor, health condition, or a medication you're taking, it may be possible to reverse it by addressing the underlying cause. Surgery may also cure ED in some cases. On the other hand, medications treat ED symptoms and can improve ED but do not cure the underlying condition.How many hours can a guy stay hard? ›
The average duration of erections is highly varied, but between 7-13 minutes before ejaculation is typically ideal, and anything longer than 3-4 hours is a medical emergency.Why do men get morning wood? ›
The parasympathetic nervous system is active when you're asleep, so erections sometimes happen in your sleep. The term “morning wood” is actually a misnomer; penises can become erect and then flaccid again several times in the course of one night. You're just more likely to notice it when you wake up.How many boners a day are normal? ›
People with penises have an average of 11 erections per day and three to five more each night, but everyone is different. There are numerous factors that can affect how often you get hard, like your age, hormone levels, and lifestyle.Can tadalafil make you hard? ›
Tadalafil is in a class of medications called phosphodiesterase (PDE) inhibitors. It works to treat erectile dysfunction by increasing blood flow to the penis during sexual stimulation. This increased blood flow can cause an erection.Does tadalafil increase size? ›
found no difference in penile size between pre and postoperative measurements with the use of full dose PDE5-I on demand (8). We found a significant decrease in all penile measurements in control patients (not using Tadalafil) at 3rd postoperative month when compared with preoperative measurements (p = 0.001).Can you take tadalafil forever? ›
Conclusion: Tadalafil at doses of 5, 10, or 20mg taken as needed up to once daily for 18 to 24 months was safe and well tolerated. These findings support the long-term use of tadalafil in the clinical management of erectile dysfunction.Why is tadalafil not effective? ›
Poor control of high blood pressure, high cholesterol, poor control of diabetes, and weight gain are some of the common causes of why tadalafil (Cialis) may stop working well. Addressing underlying problems is important not only for sexual health but also for heart health.
Which brand of tadalafil is best? ›
- Amore 36 - Chemo Biological [Tadalafil] Strength. ...
- Erectalis - Cipla [Tadalafil] Strength. ...
- Forzest - Ranbaxy [Tadalafil] Strength. ...
- Golmal - Jpee Drugs [Tadalafil] Strength. ...
- Manforce More - Mankind [Tadalafil] Strength. ...
- Megalis - Macleods [Tadalafil] Strength. ...
- Oneaid - BMW [Tadalafil] Strength. ...
- Popup - AHPL [Tadalafil] Strength.
Cialis is taken orally before sexual activity, not more than once daily. Cialis may be taken with or without food. In some patients, the dose strength and maximum frequency of use may be adjusted. For more detailed information consult with your health care provider.How much is Cialis at Walmart? ›
Cialis is not available over the counter in the United States. It must be prescribed by a licensed medical professional.Does Medicare pay for tadalafil? ›
Do Medicare prescription drug plans cover tadalafil (Adcirca)? Yes. 70% of Medicare prescription drug plans cover this drug.Do you stay hard on Cialis? ›
To treat erectile dysfunction (ED), your doctor may have you take Cialis only as needed before sexual activity. (See the “Cialis dosage” section below to learn more.) In this case, Cialis may keep working for up to 36 hours in helping you have and maintain erections during that time.What foods to avoid when taking tadalafil? ›
Do not eat grapefruit or drink grapefruit juice while you are using this medicine. Grapefruit and grapefruit juice may change the amount of this medicine that is absorbed in the body. Do not take other medicines unless they have been discussed with your doctor.Does Cialis make you harder longer? ›
Taking Cialis daily will make it easier for you to get and keep an erection for as long as you regularly take the medication. If you are only taking a higher dose of Cialis as needed, the ability to get an erection could last up to 36 hours, for some people.What can I drink to get hard? ›
Feel free to drink more caffeine
Love coffee or tea? Great! A 2005 review showed that caffeine may improve blood flow and relax the muscles that help you get and keep an erection. Try to keep it to black coffee, unsweetened tea, and caffeinated drinks without sweeteners.
Which ED medication has the least side effects? According to the Boston University School of Medicine, vardenafil (Levitra) may have the least potential for side effects because it's 10 times more biochemically potent than sildenafil (Viagra) and therefore requires a lower dose to facilitate an erection.
Is Cialis better than sildenafil? ›
The 'as required' Tadalafil (generic Cialis) has an advantage over Sildenafil in that it lasts a lot longer – up to 36 hours (compared with 4-5 hours for Sildenafil). Some men prefer this as it allows for more spontaneity.What are the top 3 erectile dysfunction pills? ›
- Sildenafil (Viagra). This medication is most effective when taken on an empty stomach one hour before sex. ...
- Vardenafil (Levitra, Staxyn). This medication also is most effective when taken one hour before sex and can be taken with or without food. ...
- Tadalafil (Cialis). ...
- Avanafil (Stendra).
What important information should you know about Cialis? CIALIS can cause your blood pressure to drop suddenly to an unsafe level if it is taken with any nitrate medication. You could get dizzy, faint or have a heart attack or stroke. Tell your healthcare provider that you take Cialis.Is there a pill stronger than Cialis? ›
Structurally vardenafil (Levitra) is similar to sildenafil, while tadalafil (Cialis) is very different. Vardenafil (Levitra) is almost 10 times more biochemically potent than sildenafil, therefore a lower dose is needed to facilitate the penile erection, potentially resulting in less side effects.