Erectile dysfunction (ED) is a common condition affecting up to 30 million people in the United States. ED is the inability to achieve and/or maintain an erection, and it can be caused by various factors, such as certain medical conditions or age.
Phosphodiesterase inhibitors (also known as PDE5 inhibitors) are a class of drugs commonly used to treat ED. Two drugs in this class are Levitra (vardenafil) and Viagra (sildenafil).
Levitra is no longer available as a brand-name drug in the United States, so it is now prescribed in its generic form, vardenafil (the active ingredient of Levitra).
This article will review important information about both medications.
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Vardenafil vs. Viagra: Key Similarities and Differences
Vardenafil is the active ingredient in Levitra. Levitra is no longer available as a brand-name drug in the United States.
Although healthcare providers sometimes refer to the drug as Levitra and write the prescription as Levitra, pharmacies will dispense vardenafil.
The chart below outlines some key similarities and differences between the two Food and Drug Administration (FDA)–approved prescription medications.
| Comparison of Vardenafil and Viagra | ||
|---|---|---|
| Levitra | Viagra | |
| Active ingredient | Vardenafil | Sildenafil |
| Brand or generic status | Available in generic only | Available in both brand and generic formulations |
| Dosages available | 2.5 milligram (mg), 5 mg, 10 mg, 20 mg oral tablets | 25 mg, 50 mg, 100 mg oral tablets |
| Usual dose | 5 mg, 10 mg, or 20 mg up to once per day | 25 mg, 50 mg, or 100 mg mg up to once per day |
| How long does it take to work? | 60 minutes | 60 minutes |
| How long do the effects last? | Up to four hours | Up to four hours |
How Do Vardenafil and Viagra Work?
PDE5 inhibitors, including vardenafil and Viagra, work in the same way.
When combined with sexual stimulation, they help increase blood flow to the penis. The increased blood flow can lead to an erection. It is important to note that these medications do not cure ED. They also do not prevent pregnancy or sexually transmitted infections (STIs).
How Long Do They Take to Work?
Both medications reach maximum effect anywhere from 30 minutes to two hours after taking a dose, with a median time of 60 minutes.
How Long Do They Last?
Both medications can last up to about four hours after taking them.
Does Food Affect How ED Drugs Work?
Some research has shown vardenafil to be affected by a high-fat meal. However, changes in dosage or food intake are not required based on clinical studies. The prescribing information states that vardenafil can be taken with or without food.
Like vardenafil, Viagra can also be taken with or without food. However, taking Viagra with a high-fat meal can make the medication take about an hour longer to work.
Other Examples of PDE5 Inhibitors
In addition to vardenafil and Viagra, there are several other PDE5 inhibitors. They include Stendra (avanafil) and Cialis (tadalafil).
Something to note is that the ingredients in some PDE5 inhibitors are also available under the same or different brand names and treat different conditions. For example, Revatio contains sildenafil, the same ingredient as Viagra, but it is used to treat pulmonary arterial hypertension (high blood pressure in the lungs). Healthcare providers also prescribe lower doses of Cialis to treat benign prostatic hyperplasia (BPH).
Which One Is More Effective?
There are few studies directly comparing vardenafil with sildenafil.
One older study compared three ED drugs: vardenafil, sildenafil, and tadalafil. The study found that vardenafil was more potent (strong) than sildenafil. However, both drugs were found to be similarly effective in treating ED.
Notably, tadalafil, the ingredient in Cialis, was preferred, possibly because it lasted longer. However, it was still similarly effective as the other ED medicines.
Another study found that both vardenafil and sildenafil were well-tolerated, with vardenafil performing better than sildenafil.
Overall, both medications are generally effective for treating ED. The American Urological Association Guidelines do not recommend any one treatment over another as long as it is appropriate for the individual.
Experts also recommend other aspects of treatment for ED, such as referral to a mental health professional and making lifestyle changes. Lifestyle changes that may help include dietary changes and increased exercise.
Side Effects: Which One Is More Tolerable?
Common side effects of vardenafil include:
- Headache
- Upset stomach
- Heartburn
- Flushing (a feeling of warmth)
- Stuffy nose
- Runny nose
- Flu-like symptoms
Common side effects of Viagra include:
- Headache
- Heartburn
- Stomach problems like nausea or diarrhea
- Flushing
- Nosebleeds
- Numbness, burning, or tingling of the hands, arms, feet, or legs
- Pain in the muscles, back, arms, or legs
- Sensitivity to light
- Stuffy nose
A serious eye problem called nonarteritic anterior ischemic optic neuropathy (NAION) could occur when taking vardenafil or Viagra.
If you have vision changes or vision loss in one or both eyes, stop taking vardenafil or Viagra and get medical attention right away. People with a history of NAION or who have what is known as a "crowded" optic disc are at higher risk. Some people will experience color vision changes, like seeing blue in certain objects or having trouble differentiating between blue and green.
Also, tell your healthcare provider if you have had any heart problems. Since there are some heart-related risks associated with sex, they may advise you not to use ED medications for sexual activity.
When to Seek Medical Attention
Seek medical help immediately if:
- You have an erection lasting more than four hours.
- You have symptoms of an allergic reaction, such as hives, difficulty breathing, or swelling of the face, lips, tongue, or throat.
- You have vision changes or vision loss in one or both eyes.
Drug Interactions
Vardenafil or Viagra interact with various drugs, so be sure to tell your healthcare provider about all of the medications you take, including prescription and over-the-counter (OTC) drugs, vitamins, and supplements.
Vardenafil or Viagra should never be taken with nitrate drugs such as isosorbide mononitrate or nitroglycerin.
Vardenafil or Viagra can also interact with other medications, such as:
- Alpha blockers, which are used to treat BPH and high blood pressure: Examples include Flomax (tamsulosin) and Uroxatral (alfuzosin)
- Other blood pressure medications, such as Norvasc (amlodipine)
- Norvir (ritonavir)
- Certain antifungals, such as ketoconazole and itraconazole
- Erythromycin
How to Take Vardenafil vs. Viagra
To get the best results, follow the instructions on your medication's label for taking it. Generally, Viagra and vardenafil have similar recommendations for how to take them, which are:
- Both should be taken about 60 minutes before sex for optimal response. However, Viagra can be taken anywhere between 30 minutes and up to four hours before sexual activity.
- Sexual stimulation is required for the medication to take effect.
- Do not take more than one tablet (regardless of dosage) in a 24-hour period.
Dosage recommendations for vardenafil include:
- Starting dose: 10 mg
- Maximum dose: 20 mg
- Maximum dosing frequency: Once per day
Dosage recommendations for Viagra include:
- Starting dose: 50 mg
- Maximum dose: 100 mg
- Maximum dosing frequency: Once per day
If your results with either medication are not as expected, consult your healthcare provider for professional medical advice. You may need a higher or lower dose or a different medication.
Vardenafil vs. Viagra vs. Cialis
Cialis is a commonly prescribed medication for ED. Its active ingredient is tadalafil.
Like vardenafil and Viagra, Cialis takes about 60 minutes to work and must be used in combination with sexual stimulation.
However, Cialis can last much longer. One dose of Cialis may last up to 36 hours. There are two ways to take Cialis. The first way is similar to vardenafil or Viagra, which is to take it about an hour before sexual activity.
Cialis can also be taken at a low dose once a day regularly, without regard to sexual activity. Then, sexual activity can occur at any time in combination with stimulation.
Coping With Erectile Dysfunction
Summary
Vardenafil and Viagra are commonly prescribed drugs used to treat ED. In combination with sexual stimulation, they can help with achieving and maintaining an erection.
Both of these medications are part of a class of drugs called PDE5 inhibitors. PDE5 inhibitors work by increasing blood flow to the penis. Because they are in the same drug class, they have many similarities but also some differences as well.
Overall, there is no "best" treatment for ED since all PDE5 inhibitors are generally effective options. You can also try other methods, such as lifestyle changes. Consult your healthcare provider for more information and medical advice on what might work for you.
13 Sources
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.
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Rubio-Aurioles E, Porst H, Eardley I, et al. Comparing vardenafil and sildenafil in the treatment of men with erectile dysfunction and risk factors for cardiovascular disease: a randomized, double-blind, pooled crossover study.J Sex Med. 2006;3(6):1037-1049. doi:10.1111/j.1743-6109.2006.00310.x
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:max_bytes(150000):strip_icc()/IMG_9695-8b4dc875a72440b48ade68c160fc970b-0f69e10a6856432c81f7663e477daebd.jpg "Levitra (Vardenafil) vs. Viagra (Sildenafil) for ED (2)")
By Karen Berger, PharmD
Karen Berger, PharmD, is a community pharmacist and medical writer/reviewer.
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