Viagra — the “blue pill,” and Cialis — the “weekend pill,” both have a proven track record in treating erectile dysfunction (ED). ED or impotence is becoming a growing concern worldwide. It’s affecting both older and younger men, regardless of the factors behind the problem — physical or lifestyle — oral ED medications have high success rates.
Viagra and Cialis both help men get and maintain an erection hard enough for sexual intercourse. However, they have different dosages, costs, side effects, and user reviews. So, Cialis Vs. Viagra — which ED drug is the best?
It’s important to understand the difference between these medicines to determine which is right for you.
Table of Contents
Difference between Viagra and Cialis – How They Work
How erections work in normal condition
During sexual arousal, nitric oxide (NO) is produced. It happens in the cavernous nerves and the whole endothelial system of the penis. Then NO diffuses into the neighboring vascular smooth muscle.
There, it helps produce cyclic guanosine monophosphate (cGMP). cGMP and NO together help with “vasodilation” or “vasorelaxation” in erectile tissue (corpora cavernosa). So, blood vessels can open or dilate. This increases blood flow to the penis and helps you get an erection.
Cialis and Viagra contain tadalafil and sildenafil, respectively. Both belong to the PDE5 inhibitors group of medications. Both are approved by the US Food and Drug Administration (FDA) as prescription-only ED pills. They cause smooth muscle relaxation and increase blood flow to help with erections.
Source: New Approaches in Oncology for Repositioning Drugs: The Case of PDE5 Inhibitor Sildenafil, Frontiers in Oncology
In erectile dysfunction (impotence)
Sometimes, an enzyme called PDE5 or phosphodiesterase 5 causes a glitch in this process. When PDE5 works too quickly, it breaks down cGMP faster than desired, abruptly stopping the erection.
Mechanism of action of ED meds
These medications work by inhibiting PDE5, thus fixing the glitch in the physiology of erection. Less is the action of PDE5, and more cGMP is available. Increased NO-cGMP activity leads to smooth muscle relaxation and blood flow to get harder erections.
These ED tablets will not work when there’s not enough sexual stimulation. Desire and arousal are necessary for erection to occur. Drugs can help with those physiological responses during arousal. They can’t activate an erection on their own.
There isn’t a major difference in how they work. The main difference rests in their pharmacokinetics (i.e., how your body uses these drugs, how quickly they are broken down, etc.).
Cialis vs Viagra – How Long Do They Last?
A study published in Patient Preference and Adherence Journal compares these medications and finds the results below.
Source: Patient preference and satisfaction in erectile dysfunction therapy: a comparison of the three phosphodiesterase-5 inhibitors sildenafil, vardenafil and tadalafil, Patient Preference and Adherence
- When taken by mouth, tadalafil is about 80% bioavailable. This means 80% of the medicine is ready to be absorbed and used by your body, compared to 40% bioavailability of sildenafil.
- In the above figure, Tmax refers to the time for maximum plasma concentration or peak plasma concentration. When the drug reaches maximum concentration in the bloodstream, it will have the strongest effects.
This indicates that the highest concentration of sildenafil (Viagra) in your blood will be observed in 1 hour. For tadalafil, the highest drug concentration takes place in 2 hours after administration.
- The onset of time means the time it takes for the drug to begin working. As shown in the data above, tadalafil 20 mg may start working more quickly than a 100 mg dose of sildenafil.
- T1/2 indicates “half-life,” or the time your body takes to reduce the drug to half of its original amount. As concentrations in plasma decline, the effects of the drug start wearing off.
However, this doesn’t mean your body has flushed out the drug yet.
- Sildenafil may take almost a day to be out of your system. Tadalafil, on the other hand, may take about 72 hours to leave your body.
So, Viagra (sildenafil) lasts for 4-6 hours, and it’s taken 30–60 minutes before having sex.
The effects of Cialis (tadalafil) last much longer than Viagra or any other PDE5 inhibitor. The pill is taken orally 20 minutes to 2 hours before sex, and the effects may last for 36 hours. However, it can remain in your system for 3 days.
Source: Time/duration effectiveness of sildenafil versus tadalafil in the treatment of erectile dysfunction in male spinal cord-injured patients, Nature
Longer duration of effects means you don’t have to plan your sex exactly around the time you take the pill. The 36-hour long window makes Cialis a good choice for couples who think that sex is more satisfying when it’s spontaneous.
As we see, dosage options are crucial in deciding which ED drug will give you the erection you expect.
Dosage and Frequency
Cialis Dosage
Cialis tablets (tadalafil) are available in different strengths, e.g., 2.5 mg, 5 mg, 10 mg, and 20 mg. There is ongoing and new research on higher doses of tadalafil oral tablets, e.g., 40 mg or 60 mg. But these doses don’t apply to most ED cases.
The lower strengths (e.g., 2.5 mg) are used as “once-daily Cialis“. The higher doses are used “on demand” before sex.
Viagra dosage
Viagra has different strengths ranging from 25 mg, 50 mg and 100 mg. In special cases, with the most stubborn Erectile Dysfunction, people may benefit from 120 mg to 150 mg and even 200 mg doses. But those cases are rare.
The typical highest recommended Viagra dosage is 100 mg not more than once in 24 hours. That’s taken on an as-needed basis.
Some experts believe that sildenafil can be used as a “once-daily” treatment for ED too. For example, Professor Irwin Goldstein of Boston University, Massachusetts, recommends this dosage.
However, most urologists would still recommend tadalafil over sildenafil for daily use.
What’s the right dose for you?
The main dosage difference between Viagra and Cialis is the frequency. Viagra isn’t usually taken every day. A Viagra tablet is taken as needed before sex. However, for daily use, a low dose of Cialis is more appropriate.
So, the Cialis daily dose is ideal for men and their partners who have sex at least two days a week.
Viagra is suitable for those who do not have sex as often. They may use it for the night without its effects lingering in the following days. Since the duration of action is shorter, so is the duration of side effects.
The right dosage depends on your condition, your metabolism, age, and other factors. Only a healthcare professional can determine that after evaluating your overall health.
Effectiveness of Viagra vs Cialis
All PDE5 inhibitors work similarly. However, Viagra is found to be more effective than others. Viagra’s effectiveness is 84%, while Cialis has a success rate of 81%, lagging a bit behind. Men who prefer Cialis possibly like the ED drug for its longer duration of effects.
Cialis will not lose its potency if you take it with food (even fatty, heavy meals). But absorption of Viagra will slow down if you take it with food.
Cialis vs. Viagra Hardness
Both medications help men in achieving and maintaining erections hard enough for vaginal penetration. The difference, as mentioned above, is how long they last in your body.
With Cialis, you can expect a penile hardness for up to 36 hours. Viagra supports a hard and rigid erection for up to 6 hours. Neither of these ED pills makes you harder than the other. Both are equally powerful, although used in different dosages. An increase in strength (e.g., from Viagra 50 to 100 mg) can help make erections more hard and fully rigid. Cialis 20mg, on the other hand, may help you reach optimal erection hardness.
Which Is Safer — Cialis or Viagra?
When taken as advised by a licensed healthcare professional, Cialis and Viagra are both safe and well tolerated for ED patients. Certain precautions still apply.
Interaction with grapefruit or grapefruit juice
Both medications can’t be taken with grapefruit juice or grapefruit products because grapefruit can block or slow down the CYP3A4 enzyme. CYP3A4 is key in metabolizing sildenafil (Viagra) and tadalafil (Cialis).
Mixing them with grapefruit raises the level of medication in your bloodstream, increasing side effect risk.
Drugs are metabolized (broken down) or excreted (flushed out of your system) through the liver and the kidneys. If you have a kidney or liver disease, reach out to your doctor to discuss which erectile dysfunction treatment is right for you.
Interaction with other drugs
Both ED medications can interact with certain drugs and other substances, e.g., high blood pressure medications, alpha-blockers, nitrates, PHT agents (for pulmonary hypertension), CYP3A4 inhibitors, etc.
For example, if you are taking nitrates for chest pain or other conditions, you can’t take Viagra or Cialis. The medications will make your blood pressure drop suddenly, which may cause severe side effects and can be fatal.
Pregnancy and breastfeeding
These ED pills are not known to affect women during breastfeeding or pregnancy.
Sildenafil and tadalafil are both considered safe for fetuses and neonates (newborns). However, there haven’t been sufficient studies on pregnant or lactating women because these erectile dysfunction treatments are meant for men.
However, if you’re a woman trying to get pregnant and your doctor has prescribed Cialis for pulmonary hypertension, let them know.
If you’re a man taking the ED pills and your wife is pregnant or trying to become pregnant, don’t worry. There won’t be any side effects on the baby or mother.
Viagra, Cialis, and alcohol
People often like to drink to get in the mood, lower inhibition, and gain confidence. While a drink or two is fine for healthy males, avoid heavy alcohol consumption when taking ED pills.
Studies show that PDE5 inhibitors with alcohol can cause blood pressure to drop to an unsafe level. This worsens side effects and may cause chest pain and coronary artery angiography.
So, if you have a health condition or are already taking some medications, it is important to talk to your doctor about the risks and benefits.
Like all medications, Cialis and Viagra may also lead to unpleasant side effects.
Side Effects – Cialis vs Viagra
The common side effects of these ED drugs are very similar, e.g., headache, facial flushing, dizziness, stuffy nose or runny nose, and stomach upset. These are relatively mild and temporary.
Here’s a patient leaflet provided by the Cambridge University Hospitals that compares sildenafil (Viagra) and tadalafil (Cialis).
Source: Cambridge University Hospitals
So, if you take Cialis, there are higher chances of backache and muscle ache. Viagra may cause vision changes (e.g., blue-tinted vision or blurred vision). With Cialis, vision problems are rare.
However, Cialis (tadalafil) lasts longer in your bloodstream. So, people taking this ED pill may experience side effects for much longer than those taking Viagra.
Cialis vs. Viagra Costs
The oral tablets under the brand names Viagra and Cialis are expensive. While Viagra is available for $65 to $150 each pill, for Cialis, you’ll have to shell out $12 to $70 for a single tablet (depending on the strength).
Viagra and Cialis are both available as the generic drugs sildenafil and tadalafil. It is important to buy ED medications from a reputed manufacturer and supplier.
You can buy ED drugs online from a reliable telehealth platform. While generic versions are also safe and effective, they are quite modestly priced.
Sildenafil is also available in more affordable versions as:
- Cenforce (Centurion Laboratories)
- Kamagra (Ajanta Pharma)
- Silagra (Cipla)
- Edegra (Sun Pharmaceutical)
- Penegra (Zydus Cadila),
- Zenegra (Alkem Laboratories)
Tadalafil is available as:
- Vidalista (Centurion Laboratories)
- Forzest (Sun Pharmaceuticals)
- Tadacip (Cipla)
So, when comparing sildenafil vs Viagra, generic sildenafil is a more pocket-friendly choice. The same goes for generic tadalafil over Cialis because generic drugs may provide value for money.
Some insurance providers give plans that cover erectile dysfunction drugs. So, make sure to check with your insurer.
| Factors | Cialis (Tadalafil) | Viagra (Sildenafil) |
| How the medication works | Inhibits PDE5 enzyme to increase blood flow to the male genital organ | Same |
How quickly it takes effect | 20 minutes to 2 hours | 30 to 60 minutes |
How long the effects last | Up to 36 hours | 4-6 hours (12 hours maximum) |
Dosage options and schedules | 2.5 mg, 5 mg (daily); 10 mg, 20 mg (as-needed) | 25 mg, 50 mg, 100 mg (as-needed) |
Bioavailability | 80% | 40% |
Peak plasma concentration (the medicine reaches its peak) | 2 hours | 1 hour |
Half life (after this time the effects usually start to wear off) | 17.5 hours | 4 hours |
Interaction with foods | Efficacy not affected by food | Slow absorption with heavy meals |
Common side effects | Headache, flushing, dizziness, stuffy nose, stomach upset are common as in Viagra. Backache, muscle pain are a high possibility. | Common side effects are similar to those of Cialis. Vision changes can occur, unlike Cialis. |
Price ranges (brand names) | $12 – $70 per tablet | $65 – $150 per tablet |
Generic version available? | Yes (e.g., Vidalista, Forzest, Tadacip) | Yes (e.g., Cenforce, Kamagra, Silagra) |
Suitability | Regular or daily use, spontaneous sex, long-lasting effects | Occasional sexual activity, on-demand use. Higher success rate. |
Final Verdict – Which Is Better?
Cialis Vs. Viagra reviews, side effects, safety, and efficacy profiles all boil down to the fact that both work well in treating ED.
Which is better for sexual performance depends on the needs of the patients (e.g., how often you have sex). Seek professional medical advice to make sure you avoid potential risks, side effects, and drug interactions.
FAQs
Which is better for sexual performance – Viagra or Cialis?
Both are effective in increasing your ability to get and maintain an erection during intercourse. However, Cialis lasts for 36 hours while Viagra works for 4 to 5 hours. Food is not known to affect the action of Cialis, whereas Viagra should be avoided with a large meal. Cialis can be used as once-daily lower doses, which may also treat conditions other than ED e.g., benign prostatic hyperplasia (BPH) or pulmonary hypertension.
Do men prefer Viagra or Cialis?
Viagra is suitable for men who like a shorter duration of effects (e.g., for a night). They may not want to have an erection the next day.
Why switch from Viagra to Cialis?
Men who would like the ED medication to remain effective for up to 1.5 days switch from Viagra to Cialis. Also, Cialis is available in lower doses and can be used once daily.
Is Cialis more expensive than Viagra?
No. Cialis, especially the lower doses, are less expensive than Viagra.
Does Cialis get you harder than Viagra?
Both are potent PDE5 inhibitors. Both can increase blood flow to the penis, raising your chances of a hard erection. So, none of them is better, stronger, or more powerful than the other. It depends on how often or frequently you expect the erections to occur.
What is the strongest erectile dysfunction pill?
40-60 mg of tadalafil or 100-200 mg of sildenafil could be among the highest doses of ED medications. Regardless of the severity of your ED, you won’t be getting a stronger dose than those options.
Does Cialis or Viagra make you bigger?
No. While these medications harden the penis and make it appear bigger by increasing blood flow, there’s no permanent increase in penis size.
What pills make you hard right away?
The four main ED oral medications are sildenafil, tadalafil, avanafil, and vardenafil. Sildenafil (Viagra) and tadalafil (Cialis) both can help you achieve an erection during sex. However, you cannot expect to get an erection straight away. You have to wait at least 30-60 minutes and receive proper sexual stimulation, i.e., be “turned on” for an erection to occur.
Does Cialis or Viagra keep you hard after cumming?
No. After cumming or orgasm, you’ll lose the erection. However, studies show that ED pills can make your “refractory period” shorter. After the refractory period (the interval between the erections), you shouldn’t have difficulty in getting another erection.
What is the most successful ED treatment?
Oral medications, such as sildenafil, tadalafil, avanafil, and vardenafil, are among the most commonly used ED treatments. They have high success rates across a range of demographics.
Can I take 2 Viagra 100?
No. Do not take two ED pills at the same time or on the same day unless your doctor has advised you to do so. It can raise your risk of side effects to a dangerous level.
Why is my husband not getting erect?
Men can lose an erection from time to time. It doesn’t necessarily mean that they have a sexual dysfunction. People may lose interest in sex due to stress, work-related burnout, and tiredness. They might not have a strong erection because they have drunk too much alcohol. Still, if a man loses erection for several days or weeks, ED may be a possible cause. The best way to make sure is to check with a urologist.
Which medicine is best to last longer in bed?
The effects of Cialis last longer than other PDE5 inhibitors, i.e., the class of medications that treat erectile dysfunction by increasing blood flow to the penis. Cialis lasts for 36 hours. So, you can expect an erection anywhere between 36 minutes to 1.5 days in the presence of sexual stimulation.
But it will not increase the length of the time you take to ejaculate (release). Only PE medications can do that.Why is Cialis not getting me hard?
There could be multiple reasons why Cialis is not working, e.g., incorrect dosing or strength, lack of sexual stimulation, or other underlying medical conditions.
Is 200 mg of Viagra too much?
Yes. For most ED cases, the maximum recommended Viagra dosage is 100mg. It is highly unlikely that a healthcare provider will recommend a 200 mg dose.
Note: Sex and gender are not binary systems but a spectrum. The word “male” or “men” in our articles refers to the genders the person was assigned at birth.
References
- Burnett, A. L. (2006b). The role of nitric oxide in erectile dysfunction: Implications for medical therapy. Journal of Clinical Hypertension, 8(s12), 53–62. https://doi.org/10.1111/j.1524-6175.2006.06026.x
- Cruz-Burgos, M., Losada-Garcia, A., Cruz-Hernández, C. D., Cortés-Ramírez, S. A., Camacho-Arroyo, I., Gonzalez-Covarrubias, V., Morales-Pacheco, M., Trujillo-Bornios, S. I., & Rodríguez-Dorantes, M. (2021). New approaches in oncology for repositioning drugs: the case of PDE5 inhibitor Sildenafil. Frontiers in Oncology, 11. https://doi.org/10.3389/fonc.2021.627229
- Raheem, A. A., & Kell, P. (2009). Patient preference and satisfaction in erectile dysfunction therapy: a comparison of the three phosphodiesterase-5 inhibitors sildenafil, vardenafil and tadalafil. Patient Preference and Adherence, 99. https://doi.org/10.2147/ppa.s3349
- Del Popolo, G., Marzi, V. L., Mondaini, N., & Lombardi, G. (2004). Time/duration effectiveness of sildenafil versus tadalafil in the treatment of erectile dysfunction in male spinal cord-injured patients. Spinal Cord, 42(11), 643–648. https://doi.org/10.1038/sj.sc.3101617
- Moynihan, R. (2003, January 1). Urologist recommends daily Viagra to prevent impotence. PubMed Central (PMC). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1124975/
- Doggrell, S. A. (2005). Comparison of clinical trials with sildenafil, vardenafil and tadalafil in erectile dysfunction. Expert Opinion on Pharmacotherapy, 6(1), 75–84. https://doi.org/10.1517/14656566.6.1.75
- Coward, R., & Carson, C. (2008n). Tadalafil in the treatment of erectile dysfunction. Therapeutics and Clinical Risk Management, Volume 4, 1315–1329. https://doi.org/10.2147/tcrm.s3336
- Mulhall, J. P., Creanga, D. L., & Stecher, V. J. (2013). Improvement in erection hardness and intercourse success with first dose of sildenafil citrate 100 mg. International Journal of General Medicine, 849. https://doi.org/10.2147/ijgm.s45449
- Schwartz, B. G., & Kloner, R. A. (2010). Drug interactions with phosphodiesterase-5 inhibitors used for the treatment of erectile dysfunction or pulmonary hypertension. Circulation, 122(1), 88–95. https://doi.org/10.1161/circulationaha.110.944603
- National Institute of Child Health and Human Development. (2023, November 15). Sildenafil. Drugs and Lactation Database (LactMed®) – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK500617/
- Kim, J. N., Oh, J. J., Park, D. S., Hong, Y. K., & Yu, Y. D. (2019e). Influence of Alcohol on Phosphodiesterase 5 inhibitors Use in Middle- to Old-Aged Men: A Comparative Study of Adverse Events. Sexual Medicine, 7(4), 425–432. https://doi.org/10.1016/j.esxm.2019.07.004
- Viagra, cialis or levitra treatment for erectile dysfunction: Frequently asked questions. (n.d.). Cambridge University Hospitals. https://www.cuh.nhs.uk/patient-information/viagra-cialis-or-levitra-treatment-for-erectile-dysfunction-frequently-asked-questions/
- Ausó, E., Gómez-Vicente, V., & Esquiva, G. (2021). Visual side effects linked to sildenafil consumption: an update. Biomedicines, 9(3), 291. https://doi.org/10.3390/biomedicines9030291
Last Updated on : September 10, 2024
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