When it comes to treating erectile dysfunction, two names often come up: Viagra and Levitra. Both work by helping increase blood flow to the penis, making it easier to get and keep an erection. Though they seem similar, their differences matter. For example, Levitra is more selective in how it works, which may mean fewer vision problems for some men. Viagra, on the other hand, has been around longer and has proven effective in many studies.
So, which one works better for you? That depends on your age, health, and how your body responds.
In this article, we will explore the key differences between Viagra and Levitra, including how they work, their effectiveness, side effects, and costs.
| 🔑 Key Takeaways ➤ Both Viagra and Levitra work by blocking an enzyme that stops a natural chemical from helping blood flow to the penis. ➤ v Levitra is more precise in how it works, so some men have fewer vision issues with it. ➤ Viagra has been on the market longer and many studies show it helps most men get and keep an erection. ➤ Neither drug causes an erection without sexual excitement, so you need to be turned on for them to work. ➤ You take Viagra 30 minutes to one hour before sex (up to four hours ahead) and no more than once a day, while Levitra is taken about one hour before sex, usually once a day. ➤ Viagra and Levitra both work quickly to help men get erections, often within 10 to 30 minutes, and can last long enough to allow couples to enjoy intimacy. ➤ Both drugs can cause headaches, flushing, and stuffy nose, but Levitra may lead to fewer muscle or stomach problems. ➤ Viagra is generally much cheaper per monthly supply than Levitra, making it easier on the wallet. |
Mechanism of Action
Viagra and Levitra both help erections by blocking the enzyme that breaks down cGMP, but Levitra is more selective and may cause fewer vision side effects.
Viagra
Viagra works by boosting the effect of nitric oxide (NO), a natural chemical released during sexual stimulation. NO activates an enzyme called guanylate cyclase, which increases levels of cyclic guanosine monophosphate (cGMP) in the smooth muscle of the penis. This cGMP causes the smooth muscle to relax, allowing blood to flow in and create an erection.
Viagra itself doesn’t directly relax the muscle—it blocks phosphodiesterase type 5 (PDE5), an enzyme that normally breaks down cGMP. By stopping PDE5, Viagra keeps cGMP levels high, so the smooth muscle stays relaxed longer, making it easier to maintain an erection.
In lab studies, Viagra was shown to be highly selective, being over 80 times more selective for PDE5 compared to PDE1 and over 700 times more selective compared to PDE2, PDE3, and others. However, its selectivity for PDE5 over PDE6 is only about 10-fold, and that’s why some men report visual disturbances, since PDE6 is involved in vision.
Levitra
Levitra has a similar but slightly different mechanism. LLevitra also increases cGMP levels by inhibiting PDE5, the enzyme responsible for breaking down cGMP in the penis.
Like Viagra, Levitra needs sexual stimulation to work because that’s what triggers the NO release and cGMP production in the first place. Levitra’s strength comes from its selectivity: in lab tests, it was more than 15 times more selective for PDE5 compared to PDE6, over 130 times more selective compared to PDE1, and more than 300 to 1,000 times more selective compared to PDE11, PDE2, PDE3, PDE4, PDE7, PDE8, PDE9, and PDE10. This high selectivity may explain why Levitra produces fewer vision-related side effects.
Efficacy
Both Viagra and Levitra help most men get and keep erections, but Levitra may work a little better across all ages.
Viagra
Viagra has been studied extensively. According to a study, Viagra led to successful intercourse in 69% of men, compared to just 22% in the placebo group. Men taking Viagra also reported an average of 5.9 successful intercourse attempts per month, while those on placebo had only 1.5. This means Viagra gave most men a clear and meaningful improvement in their ability to have sex.
One study later confirmed these findings in a summary of 11 double-blind, placebo-controlled trials. They showed that after 12 weeks of Viagra treatment, 46.5% to 87% of patients across different subgroups reported improved erections, compared to 11.3% to 41.3% on placebo.
Viagra also works well in specific groups. For example, one study reported that 56% of diabetic patients had improved erections and 61% achieved at least one successful intercourse attempt, compared to 10% and 22% in the placebo group. One research also found that 76% of men after bilateral nerve-sparing prostate surgery responded to Viagra. Clearly, Viagra is effective across a wide range of men, regardless of age or health conditions.
Levitra
Levitra has shown similarly strong results in improving erectile function. According to a study, in a flexible-dose study of 323 men, Levitra improved the International Index of Erectile Function-Erectile Function (IIEF-EF) domain score by weeks 4, 8, and 12. The placebo group barely improved, going only from 13.7–15. Also, 80–86% of men on Levitra reported improved erections, compared to just 21–36% on placebo. Successful vaginal penetration (SEP2) was achieved in 84% of Levitra users at weeks 8 and 12, compared to 49–53% on placebo. Maintenance of erection (SEP3) success ranged from 58% to 74% for Levitra, compared to 22–34% with placebo.
So, what does this mean? It shows that Levitra consistently improves both the ability to achieve and maintain an erection, which leads to better sexual experiences.
Another study provided more robust evidence through a pooled analysis of 1,385 men. They reported that EF domain scores increased to nearly 20 in men aged 65 or older, up from 14 at baseline. For younger men, scores rose to 22–24, compared to 14–16 on placebo. Positive responses to the Global Assessment Question—asking if treatment improved erections—were reported by 71% of men under 45, 76% of men aged 45–64, and 85% of men aged 65 or older. Placebo rates were much lower, at just 23%, 25%, and 34%, respectively.
This tells us that Levitra works well across all ages, giving older men just as much benefit as younger men.
Onset and Duration
Viagra and Levitra both work quickly to help men get erections, often within 10 to 30 minutes, and can last long enough to allow couples to enjoy intimacy.
Viagra
According to a study, Viagra works relatively quickly. In their study, after taking a 50 mg dose, the median time for men to reach an erection hard enough for penetration was 27 minutes, with a range from 12 to 70 minutes.
Even more, 71% of the men achieved an erection within 30 minutes of taking Viagra, and 82% responded within 45 minutes. For those who reached over 60% penile rigidity, an impressive 86% reached that level within the first 30 minutes. This shows that Viagra can give men reliable results in a short time.
Moving to how long the effects last, the study also looked at a 100 mg dose. When sexual stimulation started two hours after dosing, the median duration of grade 3 or 4 erections (meaning hard enough for penetration) was 19.5 minutes. When stimulation was delayed until four hours after taking the pill, the median duration was still 5 minutes.
Overall, the effects of Viagra can last up to at least four hours. This gives couples plenty of time to be spontaneous and enjoy intimacy.
Levitra
According to a study, Levitra shows an impressively quick onset. In their large study with 732 men, they found that within just 10 minutes after taking vardenafil, many men were already able to have successful intercourse.
Specifically, within 25 minutes, 50% of men on 10 mg and 53% on 20 mg vardenafil had at least one successful erection leading to intercourse, compared to only 26% on placebo. Even more interesting, they found a statistically better response starting at 10 minutes for the 10 mg dose and at 11 minutes for the 20 mg dose.
In another study, the researchers looked at vardenafil’s orodispersible tablet (ODT) form and the regular film-coated tablet. They reported that within 15 minutes, men taking vardenafil ODT had a mean success rate of 62.5% for intercourse, while those on placebo only reached 29.4%. In the next 16-30 minute window, the success rates rose to 65.3% for vardenafil and 32.6% for placebo.
Dosage and Administration
Levitra is usually taken daily about an hour before sex, while Viagra is taken as needed 30 minutes to 4 hours before sex, but both need sexual stimulation to work.
| Medicine | Starting Dose | Timing Before Sex | Maximum Dose |
| Viagra | Usually 50 mg once as needed | 30 min–1 hr (up to 4 hrs) | 1 dose/day |
| Levitra | 10 mg once/day (5 mg for age ≥65) | ~60 minutes | 20 mg/day |
Viagra
Viagra is usually taken only when needed, about 30 minutes to 1 hour before sexual activity. You can actually take it up to 4 hours before sex, but importantly, you should not take it more than once per day. That flexibility in timing can help you plan better.
Viagra comes in several forms, including tablets and oral suspension. If you’re using the liquid form, it’s important to shake the bottle well and use the dosing syringe or a proper measuring device—never a kitchen spoon. While taking Viagra, sexual stimulation is necessary for it to work. Just like with Levitra, an erection won’t happen automatically.
If you’re using Viagra for pulmonary arterial hypertension under the brand Revatio, the dosing is three times a day, 4 to 6 hours apart, but that’s a completely separate use, so you should never mix Revatio and Viagra. It’s also wise to avoid alcohol and grapefruit products when using Viagra, since they can increase side effects.
Levitra
Levitra is typically taken as a 10 mg tablet by mouth once a day, about 60 minutes before sexual activity. If needed, you can increase the dose to 20 mg or lower it to 5 mg, depending on how well it works for you and if you have any side effects.
For older adults, 65 years or older, the usual starting dose is 5 mg once a day, also about 60 minutes before sexual activity.
For people on stable alpha blocker treatment, the starting dose is 5 mg per day. It’s important to note that sexual stimulation is required for Levitra to work—you won’t get an automatic response just by swallowing the pill. Also, if you’re using the orally disintegrating tablet (ODT) form, you shouldn’t take it with liquid. The ODT gives higher systemic exposure and is not interchangeable with the film-coated tablet.
If you have moderate liver problems (Child-Pugh B), the maximum dose should be 10 mg, and the starting dose is 5 mg. For severe liver issues (Child-Pugh C), Levitra use is avoided altogether. With kidney problems, no dose adjustment is usually needed, unless you’re on dialysis—in that case, it should be avoided.
If you’re on medications that inhibit CYP450 3A4 (like ritonavir or ketoconazole), the dose may need to be lowered sharply, sometimes to as little as 2.5 mg every 24 or 72 hours, depending on the specific drug.
Side Effects
Both Viagra and Levitra can cause headaches, flushing, and vision changes, but Levitra tends to have fewer stomach and muscle side effects.
Viagra
For Viagra, common side effects you should know about include:
- Headache
- Heartburn
- Diarrhea
- Nausea
- Flushing, which is a warm feeling or redness
- Nosebleeds
- Numbness or tingling in the arms, hands, feet, or legs
- Muscle, back, arm, or leg pain
- Changes in color vision, especially seeing a blue tinge or having trouble telling blue from green
- Sensitivity to light
- Nasal congestion
Serious side effects include:
- Sudden severe vision loss
- Blurred vision
- Sudden decrease or loss of hearing
- Ringing in the ears
- Dizziness or lightheadedness
- Fainting
- Chest pain
- Shortness of breath
- Painful erections lasting more than 4 hours
- Rash, itching, or swelling of the face, lips, tongue, or throat
Levitra
On the other hand, Levitra also has its own list of common side effects. These include:
- Headache
- Upset stomach
- Heartburn
- Flushing
- Stuffy or runny nose
- Flu-like symptoms
Serious side effects also include:
- Erection lasting longer than 4 hours
- Sudden severe vision loss
- Blurred vision
- Changes in color vision
- Dizziness
- Sudden hearing loss
- Ringing in the ears
- Swelling of the face, throat, lips, or eyes
- Hoarseness
- Difficulty breathing or swallowing
- Fainting
- Hives or rash
Cost
Viagra is much cheaper than Levitra, though both offer big savings compared to regular pharmacy prices.
Viagra
According to the Mark Cuban Cost Plus Drug Company, Viagra is incredibly affordable compared to retail prices.
Here’s what they offer:
| Strength | Quantity | Cost | Retail Price | Savings |
| 20 mg | 30 count | $6.74 | $183.60 | $176.86 |
| 50 mg | 30 count | $7.29 | $1,098.30 | $1,091.01 |
Price of Levitra
Now, let’s look at Levitra. The prices here are much higher than sildenafil, but the savings over retail are still massive.
| Strength | Quantity | Cost | Retail Price | Savings |
| 10 mg | 30 count | $57.40 | $1,200.00 | $1,142.60 |
| 20 mg | 30 count | $57.10 | $1,167.90 | $1,110.80 |
Wrap Up
Viagra has a longer track record and often costs less, while Levitra may cause fewer vision side effects and works well for men of all ages. Timing matters, so it’s important to follow the right dose and plan ahead. Side effects can happen with either option, so knowing what to expect helps you stay safe.
So, which should you pick? Talk with your doctor to find the right fit.
Frequently Asked Questions
Can I take these with food?
Levitra is fine with food, however Viagra absorption can be affected by a heavy or fatty meal. Try to avoid big meals with Viagra.
Do they work without sexual arousal?
No. You still need to be sexually aroused or engage in foreplay for them to work.
How long do the effects last?
Levitra lasts about 5 hours. Viagra lasts around 4 hours. Neither will give you a constant erection—just help when you’re aroused.
Can I buy a cheaper version?
Yes! Viagra has a generic version called sildenafil. Levitra’s generic, vardenafil, may also be available.
Sources
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