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    How to use Viagra for best results

    On this page
    1. What is Viagra?
    2. How does Viagra work?
    3. What happens when you take Viagra?
    4. How long does Viagra take to work?
    5. How does Cialis work compared to Viagra?
    6. How effective is Viagra?
    7. What factors impact Viagra’s effectiveness?
    8. Is Viagra safe?
    9. What are the side effects of Viagra?
    10. What are the alternatives to Viagra?

    Reviewed by Dr Bhavini Shah

    Viagra is the most famous treatment for erectile dysfunction and used by millions of men worldwide. But how can you use it for the best results? In this article we look at how long Viagra takes to work, what it does and how long the effects last. 

    How long does Viagra take to work

    What is Viagra?

    Viagra is a blue tablet containing the active ingredient “sildenafil citrate”. It is taken by men who suffer from erectile dysfunction. It’s taken about an hour before sex to help gain and maintain an erection. Despite the common misconception, Viagra is not an aphrodisiac - any man taking Viagra will need to be sexually aroused to achieve an erection.

    Viagra is commonly available in three different dosages:

    • 25mg
    • 50mg
    • 100mg 

    The dosage you can take will vary depending on the person. Sometimes it may need to be increased or decreased by your doctor.    

    How does Viagra work?

    Viagra relaxes the muscle cells in the blood vessels supplying the penis, allowing an increased blood flow. Erections occur when blood flows into the penis.

    When the brain becomes aroused, it sends signals to the penis which allows blood-flow to increase in the erectile tissue. Viagra works by increasing the blood flow to the penis and making it easy to gain and maintain an erection.

    Read our Viagra information page for a more detailed explanation of this process.

    What happens when you take Viagra?

    You may have heard that taking Viagra gives you an instant, spontaneous erection. But, that’s not quite how it goes. Let's take a closer look at the Viagra timeline: 

    What happens after taking Viagra

    What does Viagra do to your body?

    Viagra works with enzymes in your body to increase blood flow to your penis. Helping you gain and maintain an erection. Find out more about the chemical process involved below: 

    What Viagra does to your body

    How long does Viagra take to work?

    Generally, Viagra requires 30-60 minutes to take effect. You should take Viagra at least one hour before you intend to have sex.

    Food, alcohol and sexual stimulation can affect the time it takes Viagra to work.  

    When to use Viagra for best results?

    Taking Viagra one hour before you have sex allows the drug to reach peak concentration in your blood. Once in your system, Viagra can last for around 4 hours. So, taking it any earlier than a few hours before you have sex may mean it won’t work.

    However, Viagra won’t work on its own. You need to be sexually aroused to have an erection. Taking it sober on an empty stomach can bring the best results. 

    Does Viagra make you last longer?

    Viagra won’t make you last longer in bed, see our guide for helpful tips. But, as shown in independent studies, Viagra lasts for around four to six hours. Typically, it takes effect 30-60 minutes after you take it. You'll need to be sexually aroused and not have eaten a fatty meal within the past few hours.

    Once the effects of Viagra have worn off, it is important that you do not take any more within 24 hours. This means you should not take Viagra in combination with any other ED tablets.  

    How does Cialis work compared to Viagra?

    Most ED treatments last for the same amount of time as Viagra, however Cialis (tadalafil) is one exception.

    Dr Bhavini Shah explains “if you are looking for an erectile dysfunction medicine that will last for longer than six hours, then Cialis may be right for you. Taken correctly (30 minutes before sex, without alcohol) Cialis can last for up to 36 hours.”

    She continues “finding the right ED medication for you will be influenced by your health. Our clinicians will review your online questionnaire to make sure any treatments are safe for you to take.“

    The table below gives some more details about the effects of ED medicines: 

    Erectile dysfunction comparison table

    How effective is Viagra?

    Viagra has been shown to be effective in two thirds of men with erectile dysfunction. Viagra’s effectiveness is decreased if you take it after a heavy meal or consuming large amounts of alcohol. Without sexual stimulation Viagra won’t produce any results.

    In clinical trials:

    • A 25mg dose of Viagra was effective for 62% of men
    • A 100mg dose of Viagra was effective for 82% of men 

    The underlying cause and severity of your erectile dysfunction also impacts on how successfully you respond to Viagra. Don’t worry if you do not experience effective results the first time you take Viagra. This is not uncommon. Doctors recommend trying Viagra up to eight times before moving to a higher dosage or exploring an alternative treatment

    What factors impact Viagra’s effectiveness?

    There’s lots of different things that can impact how well Viagra works, so if it doesn’t work the first time, don’t panic. We recommend trying it at least eight times before changing the dosage or treatment. 

    Some things that can impact Viagra’s effectiveness include:

    Food

    Eating any meal before you take Viagra will cause the medicine to take effect more slowly. Fatty meals can make it harder for Viagra to enter the bloodstream. Ideally you should take Viagra on an empty stomach. This doesn’t mean starving yourself. Just leave two hours after eating before taking Viagra.

    Find out more about the impact of food on ED

    Alcohol

    Drinking more than one or two units of alcohol will make Viagra less effective. Studies have shown excessive alcohol can compromise erections regardless of erectile dysfunction.

    Sexual stimulation

    Viagra requires arousal and sexual stimulation to take effect. It won’t give you an erection on its own. 

    Is Viagra safe?

    While most men with erectile dysfunction should be able to use Viagra. There are some exceptions. If you fall into the following categories, you shouldn't use Viagra or any other ED medicines.

    Viagra is not safe if you:

    • are taking nitrates
    • use recreational drugs that contain nitrates, such as poppers
    • have severe heart or liver problems
    • have recently had a stroke or heart attack
    • have taken alpha-blockers within the past 6 hours
    • have already taken Viagra or another type of ED medicine within the past 24 hours
    • don't experience erectile dysfunction
    • are a woman 

    You should only get Viagra through a prescription from a medical professional. Although there are a lot of websites which offer cheap erectile dysfunction medicines. It's almost impossible to be sure where these come from and whether they are safe to take.

    If you do want to start taking Viagra, speak to your GP. Or use a trusted and regulated Online Doctor service.  

    Which dosage is safe for me?

    When you order Viagra, a doctor will prescribe the safest dosage for you. If you find you're having unwanted side effects or it's working for you, you may need to change your dosage.

    “Keep in mind that you will need to try a dosage of Viagra at least eight times before changing to a higher dosage. Sometimes it takes a while to begin working.” - Dr Bhavini Shah 

    What are the side effects of Viagra?

    Most men can take Viagra without experiencing any side effects. However, as with all medicines, there are some risks. These include:

    • nausea
    • headache
    • blocked nose
    • indigestion
    • flushing (redness in the face)
    • dizziness
    • blurred vision

    For a full list of side effects, refer to the information on your medication. If you are experiencing frequent unpleasant side effects from Viagra, stop taking it and speak to your doctor.

    What are the alternatives to Viagra?

    Prescription treatments

    Some men don’t respond successfully to Viagra but there are many alternative treatments for erectile dysfunction. Other ED medications include:

    • Levitra: Similar to Viagra in length of effect but can be taken with meals.
    • Vardenafil: Vardenafil is the active ingredient of Levitra. It is essentially the same medicine without the Levitra brand name and therefore significantly cheaper.
    • Cialis: The most expensive treatment but also the longest lasting. Cialis remains active in the body for up to 36 hours.
    • Tadalafil: Tadalafil is the active ingredient of Cialis. It is essentially the same medicine without the Cialis brand name and therefore significantly cheaper.
    • Sildenafil: Sildenafil is the active ingredient of Viagra. It is essentially the same medicine without the Viagra brand name and therefore significantly cheaper.
    • Spedra: As the name suggests, Spedra is the fastest acting ED medication. It should be taken about 15 minutes before sex
    • Vitaros: Vitaros is a cream that contains the active ingredient alprostadil. Alprostadil is a vasodilator, which means it helps to widen the blood vessels, increasing blood flow and the chances of getting an erection. 

    Vacuum pumps and constriction rings 

    Vacuum pumps are a handheld device you can use to create a vacuum around the penis. This encourages blood flow, which can create an erection. 

    Constriction rings work by keeping the penis erect and can help men who find it hard to keep an erection, rather than get one in the first place. The ring is placed around the base of the penis, this traps blood in the erect penis, making it harder to lose an erection.

    Psychological treatment 

    Some men find that therapy can help with their erectile dysfunction, particularly if it’s rooted in anxiety.

    Physical treatment 

    It’s very rare, but a number of men do have surgery for ED each year. This is a last resort as it is a fairly invasive procedure. The surgery involves placing a prosthesis in the penis.  

    Conclusion

    When it comes to what Viagra does there a few key takeaways:

    • It won’t increase your sex drive or interest in sex
    • It can help you get and keep an erection
    • It can cause mild side effects which are usually temporary
    • You’ll need a prescription to use Viagra 

    To order Viagra from Online Doctor, visit our secure online clinic.

    References

    www.nhs.uk/medicines/sildenafil-viagra/
    www.medicines.org.uk/emc/medicine/30907
    www.medicines.org.uk/emc/product/9472/pil#gref
    https://www.medicines.org.uk/emc/product/8725#gref
    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1874251/
    https://bpspubs.onlinelibrary.wiley.com/doi/pdf/10.1046/j.0306-5251.2001.00034.x 
    https://www.medicines.org.uk/emc/product/1072/pil#gref
    https://www.sciencedirect.com/science/article/pii/S1879522610600371 

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