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In this article, we explore Viagra vs. Cialis for erectile dysfunction (ED), look at how Cialis and Viagra compare on side effects, and suggest the best places to buy them online.
Several drugs are available for treating symptoms of erectile dysfunction (ED), such as Cialis (tadalafil), Viagra (sildenafil), and Stendra (avanafil).
Cialis and Viagra have approval from the Food and Drug Administration (FDA) and share the same function. However, there are some differences between the two drugs.
Understanding the difference between Viagra and Cialis can help a person choose the most suitable option for them.
Cialis and Viagra are both phosphodiesterase 5 (PDE5) inhibitors, so they both work
The drugs act relatively quickly, but the precise timing depends on the drug.
The following table compares these two ED medications.
| Cialis | Viagra | |
|---|---|---|
| Main ingredient | tadalafil | sildenafil |
| How long it takes to work | around 30 minutes | around |
| How long it lasts | ||
| When to take it | daily, at the same time each day | 30 minutes to 4 hours before sex, but preferably 60 minutes before |
| Dosage | 5, 10, or 25 mg, up to once per day | 25, 50, or 100 mg, up to once per day |
| Price | from around $15 for 30 tablets of 25 mg of generic tadalafil | from around $15 for 30 tablets of 25 mg of generic sildenafil |
| Common side effects | • headache • flushing • indigestion • nasal congestion • back pain • muscle pain • limb pain | • headache • flushing • indigestion • nasal congestion • back pain • dizziness • rash |
| Pros | • people can take it with or without food • lasts longer than Viagra • can take the drug daily | • people should only take it when anticipating having sex • sildenafil is one of the cheaper ED medications • leaves the body quicker, which may make side effects last for a shorter amount of time |
| Cons | • may cause limb pain • stays in the body longer than Viagra, which may mean side effects last longer | • people need to take the drug a specific amount of time before sexual activity, which may not suit those who prefer more spontaneous sex • may cause dizziness and a rash |
The price of ED medication can vary widely depending on which medication a person chooses and whether they choose the generic or branded version.
Costs will also vary depending on whether a person’s insurance will cover the price of the medication. People always need to contact their insurance provider to see which medication it covers. Some companies may not offer coverage for branded medication.
Websites such as Optum Perks find and compare prices of medication and may offer discounts and coupons. People may find their medication at a cheaper price using a comparison site like this.
Viagra and Cialis are both drugs that treat the symptoms of ED.
A doctor will reach
Aspects of physical and mental health can contribute to ED. Therefore, a doctor will discuss these aspects along with a person’s lifestyle habits with the individual before prescribing these drugs.
However, doctors may not prescribe these drugs to someone with a cardiovascular health issue that makes sexual activity dangerous for them.
These drugs are also unsuitable for use with certain medications. Below, learn more about medications that can interact with these drugs.
Learn more about ED and premature ejaculation in our dedicated hub.
Cialis and Viagra have many similar side effects and interactions, but there are also some variations.
Anyone considering using these drugs needs to speak with a doctor first. The drugs may not be suitable for everyone, as they may affect a person’s existing health conditions or interact with other drugs the person is taking.
Neither drug is suitable for those who have had guidance from doctors to avoid sexual activity due to cardiovascular issues or who are taking nitrates for a heart condition. Using these drugs with nitrates, alpha-blockers, or anti-hypertensives may lead to a sudden fall in blood pressure, resulting in dizziness, faintness, and possibly falls and injuries.
Additionally, grapefruit juice is a CYP3A4 inhibitor, and researchers have found that it may increase the effects of these drugs in rats.
The following table compares the possible adverse effects of Cialis and Viagra.
| Viagra | Cialis | |
|---|---|---|
| Headache | x | x |
| Nasal congestion | x | x |
| Flushing | x | x |
| Indigestion | x | x |
| Nausea | x | |
| Dizziness | x | |
| Vision changes | x | |
| Muscle aches and pains | x | x |
| Back pain | x | |
| Limb pain | x | |
| Sinusitis | ||
| Flu-like symptoms | ||
| High levels of creatine kinase | ||
| Sore throat | ||
| Vision loss | x | x |
| Priapism | x | x |
| Sudden hearing loss |
If a person experiences vision loss, priapism, or sudden hearing loss while using any of these medications, it is important to contact emergency services for immediate medical attention.
Each of the medications in this article can interact negatively with other drugs. It is important to tell a healthcare professional about any other medication a person uses to reduce the risk of negative interactions.
Cialis interactions and warnings
People should not use Cialis with the following drugs:
- nitrates
- alpha-blockers
- drugs to reduce blood pressure
- CYP3A4 inhibitors, such as ketoconazole and ritonavir, as they can increase the impact
- CYP3A4 inducers, such as rifampin, an antibiotic, as they may prevent Cialis from working
Viagra drug interactions
Viagra may interact with the following drugs:
- nitrates, such as nitroglycerin
- alpha-blockers
- drugs to decrease blood pressure
- CYP4 inhibitors, such as ritonavir, ketoconazole, and erythromycin
Other concerns
Individuals also need to ensure their product is an approved version and follow a doctor’s guidance when purchasing any of these drugs.
In 2020, for example, the
The effects of Cialis (tadalafil) can last up to 36 hours, but this only means a person can have an erection or multiple erections within that time. It does not mean they will have an erection lasting 36 hours.
Similarly, the effects of Viagra (sildenafil) can last up to 12 hours, so a person can have an erection or multiple erections within that time.
The manufacturers of Cialis recommend taking the medication around 30 minutes before sexual activity.
Cialis has a longer mechanism of action than Viagra, which means the effects last longer. However, it will not help people achieve harder erections than they would if they took Viagra.
The best drug for ED will depend on the individual. It may depend on different factors, such as other medications a person is taking and how often they intend to have sex.
People can consult a medical professional to help them decide whether Viagra or Cialis will be best for them.
Cialis and Viagra relax the muscles and increase blood flow, making it possible for people with ED to experience a lasting erection during sexual activity.
It is possible for a person to have multiple erections while the effects of the drug are still working. However, the United Kingdom’s National Health Service (NHS) states that if a person experiences an erection lasting more than 3 to 4 hours, they should seek urgent medical attention.
Different aspects of a person’s health, including their mental health, can affect their ability to have and maintain erections.
If an individual experiences difficulties maintaining an erection after taking Cialis as instructed, they need to consult a healthcare professional. A doctor can discuss why this may be happening.
The best drug for ED will depend on a person and various factors, such as whether or not the person has sex regularly, other medications they are taking, and the cost and availability of the ED drugs.
Individuals can consult a healthcare professional to help them decide whether Cialis or Viagra will be best for them.
Cialis and Viagra can help a person with erectile dysfunction (ED) get and maintain an erection.
There are many side effects and interactions to consider. However, these drugs can help a person treat ED and engage in sexual activity.
It is of note that none of these drugs will provide sexual stimulation. A person will need stimulation to have an erection.
The only way to decide on the best drug may be through trial and error. Working directly with a doctor can help a person track side effects and decide which drug is most suitable for them.