Cialis (tadalafil) vs. Viagra (sildenafil)

In most cases, Viagra leaves the body in about 6 to 8 hours, and it’s taken “as needed” about 60 minutes before sex. The effects of Cialis, however, can last for up to 36 hours. For this reason, you can take a lower dose of the drug at the same time once daily, rather than just before you have sex. This can come in handy if you are unsure when sex may occur and can give you more flexibility.

Cialis vs. Viagra: similarities and differences

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

People seeking medical treatment for erectile dysfunction (ED) may feel overwhelmed by the options available, especially if their healthcare provider recommends an ED medication.

When searching for a treatment for ED, it’s important to know the differences between drugs like Viagra and Cialis, two commonly prescribed ED treatments. A key difference between Cialis and Viagra is how long the effects of the drug last in your body. Read on to learn more about their similarities and differences.

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What are erectile dysfunction drugs?

Viagra (active ingredient sildenafil) and Cialis (active ingredient tadalafil) are drugs commonly used to treat erectile dysfunction (ED). ED is a common sexual dysfunction that may cause difficulties getting an erection, keeping an erection, or having morning erections. It affects 30–50 million American men and can prevent people from having a satisfying sex life (Sooriyamoorthy, 2021).

Both Viagra (see Important Safety Information) and Cialis (see Important Safety Information) are phosphodiesterase type-5 enzyme (PDE-5) inhibitors. These drugs enhance blood flow to the penis, thereby improving erections. Other erectile dysfunction treatments in the PDE-5 inhibitor category include vardenafil (brand name Levitra) and avanafil (brand name Stendra).

None of these drugs are magic pills. While PDE-5 inhibitors are effective at treating ED, they require arousal and sexual stimulation to work.

What is Viagra?

Viagra (sildenafil) was the first drug FDA-approved to treat erectile dysfunction. Sildenafil, the active ingredient in Viagra, may also be used to treat pulmonary arterial hypertension (under the brand name Revatio, see Important Safety Information).

Some healthcare providers may use it “off-label” to treat conditions other than what’s FDA-approved. These conditions may include female sexual arousal disorder and Raynaud’s phenomenon. Occasionally, Viagra may also be used as an additional treatment for altitude-induced hypoxemia (altitude sickness) (Smith, 2021).

What is Cialis?

Cialis (tadalafil) is an FDA-approved treatment for erectile dysfunction and benign prostatic hyperplasia, a type of enlarged prostate. Under the brand name Adcirca, it can be used to treat pulmonary arterial hypertension. Like Viagra, some providers use it off-label to treat Raynaud’s phenomenon (UpToDate, n.d.).

The male refractory period: can Viagra shorten it?

What’s better: Viagra or Cialis?

Viagra and Cialis are both effective at treating erectile dysfunction when used as directed. One study comparing the two drugs showed that they were equally effective in treating erectile dysfunction (Gong, 2017).

However, differences between Cialis and Viagra might make one drug better for your lifestyle than the other. Read on to learn why Viagra or Cialis might be the right choice for you.

How fast do they work?

Viagra and Cialis take approximately the same amount of time to work. Let’s look at each a little more closely.

Viagra

Most people who take Viagra notice that it starts working around an hour after taking it, but it can be effective in as little as 30 minutes. It can take up to two hours to start working for some people. The recommendation is to take Viagra about 60 minutes before sexual activity. You can take it with food or on an empty stomach. However, if you take it with a high-fat meal, it may take longer to start working (DailyMed-a, 2022; Zucchi, 2019).

Cialis

For most people, Cialis starts working in about 30 minutes. Like Viagra, you can take it with or without food (DailyMed-b, 2022; Zucchi, 2019).

How long do they last?

One of the key differences between Viagra and Cialis is how long the effects last in your body.

In most cases, Viagra leaves the body in about 6 to 8 hours, and it’s taken “as needed” about 60 minutes before sex. The effects of Cialis, however, can last for up to 36 hours. For this reason, you can take a lower dose of the drug at the same time once daily, rather than just before you have sex. This can come in handy if you are unsure when sex may occur and can give you more flexibility.

With both drugs, other factors may impact how long you are able to get and keep an erection (e.g., dosage, health conditions, additional medications, and overall health). And you need to be sexually aroused for either drug to work (in other words, you won’t get unwanted erections after taking these drugs without being sexually aroused) (DailyMed-a, 2022).

What doses do Viagra and Cialis come in?

The dosing for these two drugs is another area where they differ.

Viagra

Sildenafil citrate (Viagra) comes in 25 mg, 50 mg, or 100 mg oral tablets.

While most people start with the 50 mg dose, your healthcare provider may recommend a higher or lower dose, depending on your medical history. The maximum daily dose for Viagra is 100 mg per day.

Cialis

Tadalafil (Cialis) is available as an oral tablet in varying strengths: 2.5 mg, 5 mg, 10 mg, and 20 mg.

When using Cialis as needed for ED, most people start with 10 mg at least 30 minutes before sex. However, if you are taking it daily for ED, you’ll likely start with 2.5 mg taken around the same time each day. Your healthcare provider may recommend a higher or lower dose depending on your medical history and other factors.

People using Cialis for BPH usually take a starting dose of 5 mg per day.

The maximum daily dose for Cialis is 20 mg per day.

Erectile dysfunction pills and medications: Viagra, Cialis, and more

Side effects of Viagra and Cialis

Since they belong to the same drug class, it’s not surprising that Viagra and Cialis have similar side effects. The risk of these side effects may depend on your medication dosage, medical conditions, and other factors.

Priapism

Priapism is a painful, prolonged erection that lasts more than 4–6 hours and is a medical emergency. If the erection is not relieved, it can lead to permanent damage to your penis. All PDE-5 inhibitors, including Viagra and Cialis, increase your risk of developing priapism. Fortunately, this is a relatively rare serious side effect (DailyMed-a, 2022; DailyMed-b, 2022).

Low blood pressure

PDE-5 inhibitors work by encouraging the penis blood vessels to relax, allowing more blood to flow into the penis to maintain the erection. However, they affect your blood vessels throughout your body, not just those in the penis. When your vessels relax (or dilate), it causes your blood pressure to drop.

In some cases, this is the effect we are looking for in a drug. But if you already have low blood pressure or are taking another medication to lower your blood pressure, PDE-5 inhibitors can make your blood pressure drop lower than intended, which can be dangerous (DailyMed-a, 2022; DailyMed-b, 2022).

Blurred vision

Rarely, people who take PDE-5 inhibitors report blurry vision due to an eye condition called non-arteritic ischemic optic neuropathy (NAION). This mainly happens in people with other risk factors for this condition. NAION can lead to changes in your vision that may or may not be permanent. Before starting a PDE-5 inhibitor like Viagra or Cialis, talk to your eye care professional about whether you are at an increased risk for developing NAION (DailyMed-a, 2022; DailyMed-b, 2022).

Effects on the heart

The data is murky on how PDE-5 inhibitors affect the heart. It is unclear whether any new heart issues reported in clinical trials resulted from the medications, sexual activity, or other factors. For this reason, people with preexisting risk factors for heart disease (like high blood pressure, high cholesterol, diabetes, etc.) or a history of heart attacks or strokes should get medical advice from their healthcare provider before starting Viagra or Cialis (DailyMed-a, 2022; DailyMed-b, 2022).

Aside from the rare side effects above, there are also some common side effects of both drugs.

Sildenafil vs. Viagra: what’s the difference?

Viagra side effects

The most common side effects of Viagra include (Smith, 2021):

Cialis side effects

The most common side effects of Cialis include (DailyMed-b, 2022):

  • Headaches
  • Indigestion/heartburn
  • Back pain
  • Muscle aches
  • Nasal congestion
  • Flushing
  • Pain in arms or legs

Cialis is less likely to cause facial flushing than Viagra, but more likely to cause back pain, muscle aches, and pain in arms or legs. If it occurs, the pain usually starts 12–24 hours after taking Cialis and goes away 48 hours after your last dose. People describe the back pain as diffuse lower back pain that may also affect your glutes or thighs that worsens with lying down. Fortunately, this pain is temporary and is not severe for most people (Gong, 2017; DailyMed-b, 2022).

Cialis vs. Viagra drug interactions

As with any drug, seek medical advice from your healthcare provider before starting erectile dysfunction medications, including Viagra or Cialis. Be sure to discuss your medical history, as well as any over-the-counter supplements or prescription medicines you take, so you can best prevent any potential drug interactions.

Given that both Viagra and Cialis are PDE-5 inhibitors, it comes as no surprise that they have similar drug interaction warnings.

One of the most serious drug interactions with PDE-5 inhibitors, like Viagra and Cialis, happens with nitrates, drugs often used to treat chest pain (angina) or other heart conditions. Taking these drugs with PDE-5 inhibitors can lead to a severe drop in blood pressure with potentially fatal consequences. Examples include nitroglycerin and amyl nitrites, also called “poppers” (DailyMed-a, 2022; DailyMed-b, 2022).

Similarly, if you take alpha-blockers, you should not take Viagra or Cialis. Alpha-blockers are used to treat high blood pressure and some prostate issues like benign prostatic hyperplasia (BPH).

Since alpha-blockers lower your blood pressure, combining them with PDE5 inhibitors can again lead to a dangerous situation where your blood pressure is too low. Examples of alpha-blockers include terazosin (brand name Hytrin) and tamsulosin (brand name Flomax) (DailyMed-a, 2022; DailyMed-b, 2022).

Lastly, drugs that affect the CYP3A4 enzyme system may disrupt how your liver processes Viagra and Cialis, thereby increasing your risk of side effects. Examples of these drugs include ketoconazole, itraconazole, ritonavir, indinavir, and erythromycin. Grapefruit juice can also affect this enzyme system, so drinking large quantities could theoretically affect your sildenafil or tadalafil drug levels (DailyMed-a, 2022; DailyMed-b, 2022).

There may be other potential drug interactions with Viagra or Cialis. Seek medical advice from your pharmacist or healthcare professional if you have questions or concerns.

Viagra vs. Cialis: differences and similarities

References

  1. DailyMed. (2022-a). Viagra- sildenafil citrate tablet, film-coated. Retrieved on Feb. 3, 2022 from https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=a2a9f459-e692-4e85-83b0-a35fbf35e91b
  2. DailyMed. (2022-b). Tadalafil tablet, coated. Retrieved on Feb. 3, 2022 from https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=abcb2cda-9b3f-45f6-ad5f-c2370b0dd114
  3. Gong, B., Ma, M., Xie, W., et al. (2017). Direct comparison of tadalafil with sildenafil for the treatment of erectile dysfunction: a systematic review and meta-analysis. International Urology and Nephrology, 49(10), 1731–1740. doi:10.1007/s11255-017-1644-5. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5603624/
  4. Smith, B. P. & Babos, M. (2021). Sildenafil. StatPearls. Retrieved on Feb. 3, 2022 from https://www.ncbi.nlm.nih.gov/books/NBK558978/
  5. Sooriyamoorthy, T. & Leslie, S. W. (2021). Erectile dysfunction. StatPearls. Retrieved on Feb. 3, 2022 from https://www.ncbi.nlm.nih.gov/books/NBK562253/
  6. UpToDate. (n.d.). Tadalafil: drug information. Retrieved on Feb. 3, 2022 from https://www.uptodate.com/contents/tadalafil-drug-information
  7. Zucchi, A., Costantini, E., Scroppo, F. I., et al. (2019). The first-generation phosphodiesterase 5 inhibitors and their pharmacokinetic issue. Andrology, 7(6), 804–817. doi:10.1111/andr.12683. Retrieved from https://pubmed.ncbi.nlm.nih.gov/31350821/

Cialis (tadalafil) vs. Viagra (sildenafil)

Cialis (tadalafil) and Viagra (sildenafil) are oral drugs that are used for treating impotence (the inability to attain or maintain a penile erection) and benign prostatic hyperplasia (BPH). They are in a class of drugs called phosphodiesterase-5 (PDE5) inhibitors that also includes vardenafil (Levitra, Staxyn ODT), and avanafil (Stendra).

Penile erection is caused by the engorgement of the penis with blood. Under normal conditions, sexual stimulation leads to the production and release of nitric oxide in the penis. Nitric oxide then activates the enzyme, guanylate cyclase, which causes the production of cyclic guanosine monophosphate (cGMP). It is the cGMP that is primarily responsible for the erection by affecting the amount of blood that the blood vessels deliver and remove from the penis. Cialis and Viagra inhibit an enzyme called phosphodiesterase-5 (PDE5) which destroys the cGMP. Thus, Cialis and Viagra prevent the destruction of cGMP and allows cGMP to accumulate and persist longer. The longer cGMP persists, the more prolonged the engorgement of the penis.

SLIDESHOW

What are the side effects of Cialis and Viagra?

Cialis

If you are taking Cialis and you have nausea, chest pain or dizziness during sex, seek medical help immediately as you may have a life-threatening condition.

The most common side effects of tadalafil are:

  • low blood pressure,
  • blurred vision,
  • changes in color vision, and
  • abnormal ejaculation.
  • Priapism, or an erection that lasts more than four hours that can damage the penis

Viagra

If you are taking Viagra and you have nausea, chest pain or dizziness during sex, seek medical help immediately as you may have a life-threatening condition.

Approximately 15% of persons taking Viagra experience side effects. The most common side effects are:

  • facial flushing (1 in 10),
  • headaches (1 in 6),
  • stomach pain,
  • nasal congestion,
  • nausea,
  • dizziness,
  • rash,
  • urinary tract infections (UTIs)
  • diarrhea, and
  • an inability to differentiate between the colors green and blue.
  • Priapism, or an erection that lasts more than four hours that can damage the penis

Health News

What is the dosage of Cialis vs. Viagra?

Cialis

For most individuals, the recommended starting dose of tadalafil is 10 mg per day taken before sexual activity (tadalafil for use as needed).

Depending on the adequacy of the response or side effects, the dose may be increased to 20 mg or decreased to 5 mg a day. The effect of tadalafil may last up to 36 hours. Individuals who are taking medications that increase the blood levels of tadalafil should not exceed a total dose of 10 mg in 72 hours (See drug interactions). For once daily use without regard to sexual activity, the recommended dose is 2.5 to 5 mg daily. Tadalafil should not be taken more than once daily.

The recommended dose for BPH, or BPH and ED is 5 mg daily taken about the same time each day. Tadalafil may be taken with or without food since food does not affect its absorption from the intestine.

The dose of tadalafil may require adjustment for patients with reduced kidney or liver function.

Viagra

  • The usual recommended dose is 25 to 100 mg 1 hour before sexual activity.
  • The maximum dose is 100 mg daily.
  • The elderly (over 65 years of age) should start at 25 mg before sexual activity.
  • Sildenafil is rapidly absorbed. Maximum observed plasma concentrations are reached within 30 to 120 minutes (median 60 minutes) of oral dosing in the fasted state. When sildenafil is taken with a high fat meal, the rate of absorption is reduced, with an average delay in the time to maximal concentration of 1 hour.

QUESTION

What drugs interact with Cialis and Viagra?

Cialis

The breakdown and elimination of tadalafil from the body may be decreased by erythromycin, ketoconazole (Nizoral), itraconazole (Sporanox), indinavir (Crixivan) and ritonavir (Norvir). Therefore, these drugs may increase the levels of tadalafil in the blood. If these drugs are being used at the same time as tadalafil, the dose of tadalafil should be reduced to 10 mg every 72 hours when used as needed or 2.5 mg when used daily in order to avoid side effects from high levels of tadalafil.

Rifampin, carbamazepine (Tegretol, Tegretol XR, Equerto, Carbatrol), phenytoin (Dilantin, Dilantin-125), and phenobarbital may decrease blood levels of tadalafil, possibly reducing the effect of tadalafil.

Tadalafil exaggerates the increases in heart rate and lowering of blood pressure caused by nitrates, for example, nitroglycerin, isosorbide dinitrate (Isordil), isosorbide mononitrate (Imdur, Ismo, Monoket), nitroglycerin (Nitro-Dur, Transderm-Nitro) that are used primarily for treating heart pain (angina). In patients who take nitrates for angina, tadalafil could cause heart pain or possibly even a heart attack by exaggerating the increase in heart rate and the lowering of blood pressure. Therefore, tadalafil should not be used with nitrates.

Tadalafil also exaggerates the blood pressure lowering effects of some alpha-blocking drugs for example, terazosin (Hytrin) that primarily are used for treating high blood pressure or enlargement of the prostate (BPH). Individuals who take these alpha-blockers should be on a stable dose of the alpha-blocker before tadalafil is started. In such situations, tadalafil should be started at the lowest dose. If the patient is already taking tadalafil, the alpha-blocker should be started at the lowest dose. Combining tadalafil with alpha-blockers for treatment of BPH is not recommended.

Tadalafil and alcohol both lower blood pressure. Therefore, combining tadalafil with alcohol may cause excessive drops in blood pressure and cause dizziness, headaches, and increased heart rate.

PDE5 inhibitors may affect platelet function and therefore prolong bleeding. Tadalafil should be used cautiously in patients with bleeding disorders or active ulcers. Tadalafil should not be combined with Adcirca (another form of tadalafil) or other PDE5 inhibitors, for example, vardenafil (Levitra) or sildenafil (Viagra, Revatio).

Viagra

Viagra increases the effects of the blood pressure lowering medications. It also increases the blood pressure lowering effects of nitrates, for example, isosorbide dinitrate (Isordil), isosorbide mononitrate (Imdur, Ismo, Monoket), nitroglycerin (Nitro-Dur, Transderm-Nitro) that are used primarily for treating angina. Patients taking nitrates should not receive Viagra.

Patients should not combine Viagra with other PDE5 inhibitors (for example, vardenafil [Levitra], tadalafil [Cialis]).

Cimetidine (Tagamet), erythromycin, ketoconazole (Nizoral), itraconazole (Sporanox), atazanavir (Reyataz), and mibefradil (Posicor) can cause marked increases in the amount of Viagra in the body. Patients taking these medications should be observed carefully if sildenafil is used.

It is expected that rifampin will decrease blood levels of Viagra and probably reduce its effectiveness.

Are Cialis and Viagra safe to use while pregnant and breastfeeding?

Cialis

Tadalafil is not approved for women and has not been evaluated in women who are breastfeeding.

Viagra

Although extensive testing in animals has demonstrated no negative effects on the fetus, Viagra has not been studied in pregnant women. There is no effect on sperm count or motility of sperm in men.

It is not known whether sildenafil is excreted into breast milk.

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Summary

Cialis (tadalafil) and Viagra (sildenafil) are oral drugs that are used for treating impotence (the inability to attain or maintain a penile erection) and benign prostatic hyperplasia (BPH). They are in a class of drugs called phosphodiesterase-5 (PDE5) inhibitors that also includes vardenafil (Levitra, Staxyn ODT), and avanafil (Stendra).

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Enlarged Prostate (BPH, Benign Prostatic Hyperplasia)

Benign prostatic hyperplasia (BPH or enlarged prostate) is very common in men over 50 years of age. Half of all men over the age of 50 develop symptoms of BPH, but few need medical treatment. This noncancerous enlargement of the prostate can impede urine flow, slow the flow of urine, create the urge to urinate frequently and cause other symptoms like complete blockage of urine and urinary tract infections. More serious symptoms are urinary tract infections (UTIs) and complete blockage of the urethra, which may be a medical emergency. BPH is not cancer. Not all men with the condition need treatment, and usually is closely monitored if no symptoms are present. Treatment measures usually are reserved for men with significant symptoms, and can include medications, surgery, microwave therapy, and laser procedures. Men can prevent prostate problems by having regular medical checkups that include a prostate exam.

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Cialis Vs Viagra

Cialis and Viagra are two of the most popular erectile dysfunction treatments available today. They are commonly prescribed to men suffering from impotence to help them enjoy a normal, active sex life.

There are lots of things to consider when you’re comparing Cialis vs Viagra. Dosage, duration, other medications, and more factors should all be taken into account.

If you’re interested in using Viagra or Cialis for ED and you want to know more, we’ve created this useful guide comparing the two. We look at the difference between the two in more detail and compare which treatment might be better for you as well as considering some of the other available ED treatments.

Cialis vs Viagra: which gets you harder?

Contrary to popular belief, neither erectile dysfunction medication, Cialis or Viagra, is able to make you harder than the other. Each ED treatment is effective at helping men achieve and sustain an erection during sex.

It’s worth noting that, while both Cialis and Viagra will help you achieve a harder erection, this only works if you suffer from erectile dysfunction. If you can already achieve a strong erection without the use of ED treatments, neither Viagra nor Cialis will make you harder.

Cialis or Viagra: which is better?

Viagra and Cialis are both effective ED treatments that many men use to help them sustain an erection. Neither medication is necessarily ‘better’ than the other, but both Cialis and Viagra have some unique properties that make them suitable for different people.

One key difference between the two is how long they last. Viagra lasts for up to 5 hours, although this varies depending on the user. Cialis Daily, on the other hand, lasts for around 24 hours when taken regularly, while Cialis on-demand lasts for up to 36 hours per dose.

Another difference between Cialis and Viagra is the frequency with which they are taken. Viagra and Cialis on-demand are taken as needed before sex. Cialis Daily, however, is taken once a day, every day.

In the same vein, each medication is designed for different situations. For instance, Viagra and Cialis on-demand are suited for men who have sex infrequently. In contrast, Cialis Daily is designed for men who have sex regularly, at least twice a week.

Many customers find their erections from both Cialis and Viagra are satisfactory. If you’re unsure about which is right for you, check out our customer reviews of Cialis here.

What’s the difference between Cialis and Viagra?

While Viagra and Cialis are both medications used to treat impotence, they are not the same. Both are used to treat erectile dysfunction, but they have some key differences.

Cialis contains the active ingredient tadalafil, while Viagra contains sildenafil. Both ingredients increase blood flow to the penis to help a man get and sustain an erection.

Viagra and Cialis are generally as effective as each other.

Each tablet is taken up to 30-60 minutes before sex. Viagra lasts for up to five hours, depending on the user. Cialis 10mg and 20mg last for up to 36 hours and Cialis 2.5mg and 5mg last for up to 24 hours.

For Viagra and Cialis to work effectively, you must first be sexually aroused. They do not increase your sexual desire (libido).

You should also make lifestyle changes to increase the effectiveness of Cialis and Viagra. Quitting smoking, losing weight, and exercising regularly all make ED treatments such as Viagra and Cialis work better.

Dosage differences between Cialis and Viagra

One tablet of Cialis should be taken 30-60 minutes before sex, while a single tablet of Viagra should be taken just 30 minutes before sex. Viagra and Cialis are usually prescribed at a lower dosage at first, which is then increased according to each user’s personal needs.

The 2.5mg and 5mg dosages are known as Cialis Daily. These should be taken daily when you are having sex at least twice a week. The 10mg and 20mg dosages of Cialis, on the other hand, should be taken as required before sex.

Viagra, on the other hand, comes in three dosages:

Viagra should be taken as required before having sex.

For more information on Cialis dosage and directions for us, read our Cialis dosage page.

Do I need a prescription for Cialis or Viagra?

Cialis and Viagra can only be bought with a prescription from your doctor. However, Viagra Connect can be bought over-the-counter from your pharmacist without a prescription.

Cialis vs Viagra: side effects

Like all medications, both Cialis and Viagra can cause side effects. Below are some common side effects for both Viagra and Cialis:

  • Headache
  • Facial redness and flushing
  • Changes in vision
  • Back or muscle pain
  • Mild sickness or nausea
  • Upset stomach
  • Flushing and redness in the face
  • Headaches
  • Diarrhoea
  • Low blood pressure
  • Muscle or back pain
  • Flu-like symptoms e.g. a blocked nose or a sore throat

For more side effects of Cialis, read our dedicated Cialis side effects page here.

Viagra vs Cialis: interactions with other medicines

Like all medications, both Cialis and Viagra can interact with other medicines.

You should not take Cialis with any of the following:

  • Nitrates, such as medicine for angina
  • Alpha-blockers
  • Epilepsy medicine
  • Antibiotics
  • Pulmonary arterial hypertension (PAH) medicine
  • Some HIV treatments
  • Amyl nitrate, a recreational drug known as ‘poppers’

You should not take Viagra with any of the following:

  • Nitrates, for instance for chest pain
  • Pulmonary arterial hypertension (PAH) medicine such as riociguat
  • Amyl nitrate or ‘poppers’, a recreational drug

If you are taking any other medication and you are unsure whether Viagra or Cialis will interact with it, speak with your doctor or pharmacist first.

Sildenafil vs Cialis

Sildenafil is the active ingredient in Viagra. It is sold as both Viagra and as the generic medicine sildenafil.

Sildenafil works in the same way as Viagra, increasing blood flow to the penis to help you get and sustain an erection.

While sildenafil is chemically the same as Viagra, it is much cheaper. Consequently, sildenafil is a more cost-effective Viagra alternative.

Tadalafil vs Cialis

Cialis is the brand name for tadalafil, a medicine used to treat erectile dysfunction in men. Cialis is essentially the same as tadalafil. Consequently, there is no difference between Cialis and tadalafil.

Although tadalafil is medically the same as Cialis, it is often much cheaper. As a result, tadalafil is a more affordable alternative to Cialis.

Summary

Cialis and Viagra are both effective and popular erectile dysfunction medications. Many men use Viagra and Cialis to overcome impotence so they can enjoy a healthy sex life.

Hopefully, the information above will help you make an informed decision about the right ED treatment for you.

If you’ve decided that Cialis is the right medication for you, you can buy Cialis here from The Independent Pharmacy. Or if you think that Viagra is the right choice for you, buy Viagra here instead.

Once you’ve decided on the ED treatment for you, simply complete our quick online consultation. Once we’ve approved it, we’ll dispatch your medication the same working day (before 4pm) in plain, discreet packaging.

Sources

Similarities and Differences Between Cialis and Viagra

Medically reviewed

Table of contents

Erectile dysfunction (ED), or impotence, is the inability to achieve or sustain a firm erection long enough to enjoy sexual activity.

The condition becomes more common with older age, but young men can also experience ED: One study from 2013 found that around 25 percent of erectile dysfunction patients were 40 or younger.

It’s estimated that 30 million American men suffer from ED, and previous surveys found that 70 percent of men over age 70 suffered from the condition.

ED doesn’t have to be a “normal” part of aging.

Leaving the condition untreated can lead to more than just sexual frustration.

It can also negatively impact your relationships, mental health, and overall quality of life.

Fortunately, several prescription drugs can address your symptoms and improve your erections.

Some underlying medical conditions like diabetes and heart disease can cause ED, so it is important to see your primary care provider for an evaluation before starting any ED treatment.

Two brand-name medications, Cialis (tadalafil) and Viagra (sildenafil), have been successfully used for decades to treat patients who have been diagnosed with ED.

They are both a type of medication called phosphodiesterase type 5 inhibitors, or PDE5 inhibitors.

These relax the smooth muscle in the penis and dilate the blood vessels to improve blood flow.

When combined with sexual stimulation, these ED treatments help patients achieve and maintain an erection.

Although Cialis and Viagra are in the same class of medications and work in similar ways, there are key differences between them.

They each have unique benefits, active ingredients, side effects, and drug interactions.

For that reason, patients may find that, when it comes to improving their personal experience, one medication is a better fit than the other.

In this article, I’ll explain the differences between Cialis and Viagra, including how they work, the dosage of each drug, their effectiveness, costs, side effects, and interactions with other medications.

I’ll also outline how you can get a prescription for Cialis or Viagra, and when to talk to your doctor or other healthcare professional.