What Is Viagra?

Viagra is a prescription medicine used to treat erectile dysfunction (ED) in adult men.

Erectile dysfunction describes difficulty achieving or maintaining an erection firm enough for satisfactory sexual activity.

Viagra contains the active ingredient sildenafil, one of the most established medicines used for erectile dysfunction.

The European Commission granted Viagra an EU-wide marketing authorisation in September 1998, and that authorisation remains active.

It is available as conventional tablets in strengths of:

• 25mg
• 50mg
• 100mg

A 50mg orodispersible formulation that dissolves in the mouth is also authorised.

Viagra does not automatically produce an erection. Sexual stimulation is still required.

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What Is the Active Ingredient in Viagra?

The active ingredient in Viagra is sildenafil.

Sildenafil belongs to a group of medicines called phosphodiesterase type 5 inhibitors, usually shortened to PDE5 inhibitors.

Other erectile dysfunction medicines also belong to the PDE5 inhibitor family, although they may contain different active ingredients and have different onset times, durations and dosing instructions.

Generic sildenafil products contain the same active substance as Viagra and are approved in the EU as generic versions of the reference medicine.

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How Does Viagra Work?

During sexual stimulation, the body releases chemical signals that increase levels of a substance called cyclic guanosine monophosphate (cGMP) in the penis.

cGMP causes smooth muscle in the erectile tissue to relax, allowing more blood to flow into the penis.

An enzyme called PDE5 normally breaks cGMP down.

Sildenafil blocks PDE5, allowing cGMP activity to continue for longer.

This can improve blood flow and make it easier to achieve and maintain an erection during sexual stimulation.

Viagra does not:

• create sexual desire;
• act as an aphrodisiac;
• produce a permanent erection;
• increase testosterone directly; or
• cause an erection without sexual stimulation.

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What Is Erectile Dysfunction?

Erectile dysfunction is the persistent or recurring inability to achieve or maintain an erection sufficient for satisfactory sexual activity.

It can affect men of different ages and may be influenced by physical, psychological or lifestyle factors.

Potential contributors can include:

• cardiovascular disease;
• high blood pressure;
• diabetes;
• obesity;
• smoking;
• excessive alcohol consumption;
• certain medicines;
• stress;
• anxiety;
• depression; and
• relationship or performance concerns.

Because ED can sometimes be associated with underlying cardiovascular or metabolic problems, persistent erectile difficulties should not automatically be treated as simply a sexual-performance issue.

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Who May Be Suitable for Viagra?

Viagra is authorised for adult men with erectile dysfunction.

Suitability depends on factors including:

• medical history;
• cardiovascular health;
• blood pressure;
• current medicines;
• liver and kidney function;
• previous ED treatment;
• eye conditions; and
• other individual health considerations.

Completing a consultation does not automatically mean Viagra will be appropriate.

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How Do You Take Viagra?

The usual recommended starting dose is 50mg taken as needed approximately one hour before sexual activity.

Depending on effectiveness and tolerability, the dose may be:

• reduced to 25mg, or
• increased to 100mg.

The maximum recommended dose is 100mg, and the maximum recommended frequency is once per day.

Always follow the dose prescribed for you.

Do not increase your dose simply because a lower dose did not produce the effect you expected on one occasion.

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What Viagra Strength Should I Take?

Viagra is available in three main tablet strengths.

Viagra 25mg

The lower strength may be considered when a reduced dose is more appropriate, including in some people with particular medical circumstances or increased sensitivity to side effects.

Viagra 50mg

50mg is the usual recommended starting dose for many adult men.

Viagra 100mg

100mg is the maximum recommended dose and may be considered where a lower dose has not been sufficiently effective and the higher dose is medically appropriate.

A higher dose is not automatically better.

Higher doses can also increase the likelihood of adverse effects.

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How Long Before Sex Should I Take Viagra?

Viagra is generally taken about one hour before sexual activity.

The exact response can vary between individuals.

Factors that can influence how quickly sildenafil takes effect include:

• food intake;
• particularly heavy or fatty meals;
• alcohol;
• individual metabolism;
• other medicines; and
• the presence of sufficient sexual stimulation.

Planning ahead can therefore be useful rather than taking the tablet immediately before anticipated sexual activity.

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Does Food Affect Viagra?

Yes.

EMA information notes that taking Viagra with food can delay the onset of its effects compared with taking it without food.

A particularly large or high-fat meal may therefore mean it takes longer to notice an effect.

This does not necessarily mean the medicine has failed.

Follow the instructions supplied with your medicine.

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Does Viagra Work Without Sexual Stimulation?

No.

Sexual stimulation is required for Viagra to work.

Sildenafil supports the natural erectile response by improving the blood-flow mechanism involved in producing an erection.

It does not cause an erection independently of sexual arousal.

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How Effective Is Viagra?

Viagra has been extensively studied.

EMA’s assessment includes four principal clinical studies involving 1,690 men aged 19 to 87 years.

In fixed-dose studies, the proportion of participants reporting improved erections was approximately:

• 62% with 25mg
• 74% with 50mg
• 82% with 100mg

compared with 25% with placebo.

These figures describe groups in clinical trials and do not guarantee that Viagra will work for every individual.

Response can depend on the underlying cause of ED and other health factors.

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What If Viagra Does Not Work the First Time?

A single unsuccessful attempt does not necessarily mean sildenafil is unsuitable or ineffective.

Possible reasons include:

• insufficient sexual stimulation;
• taking the medicine after a heavy meal;
• timing;
• alcohol consumption;
• anxiety;
• incorrect dose;
• other medicines; or
• the underlying cause of erectile dysfunction.

Do not take another Viagra tablet on the same day simply because the first dose did not produce the desired result.

The maximum recommended dosing frequency is once daily.

If treatment repeatedly does not work, discuss this with an appropriate healthcare professional.

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What Are the Common Side Effects of Viagra?

Like all medicines, Viagra can cause side effects.

EMA identifies common sildenafil adverse effects including:

• headache;
• flushing;
• indigestion;
• visual disturbances, including altered colour vision or blurred vision;
• nasal congestion;
• dizziness;
• nausea; and
• hot flushes.

Side effects are not experienced by everyone.

The likelihood of some adverse effects can increase with higher doses.

Read the current patient leaflet supplied with your medicine before use.

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What Serious Viagra Side Effects Should I Know About?

Although uncommon, some symptoms require urgent medical attention.

Seek appropriate medical care if you experience severe or worrying symptoms such as:

• chest pain;
• a severe allergic reaction;
• sudden significant vision changes;
• sudden hearing problems; or
• an erection that is prolonged, painful or does not resolve normally.

Do not rely on an online product page where urgent medical assessment may be required.

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Can Viagra Be Taken With Nitrates?

No.

Viagra must not be taken with nitrate medicines, which are commonly used for angina and certain cardiovascular conditions.

Combining sildenafil with nitrates can cause a potentially dangerous fall in blood pressure.

Viagra must also not be taken with guanylate cyclase stimulators such as riociguat.

This is one of the reasons it is essential to disclose all medicines during your consultation.

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Who Should Not Take Viagra?

Viagra is not suitable for everyone.

According to EMA information, it must not be used in certain circumstances, including where:

• sexual activity is medically inadvisable because of severe cardiovascular disease;
• nitrate medicines are being used;
• riociguat or another applicable guanylate cyclase stimulator is being used;
• there has previously been certain types of vision loss such as NAION;
• severe hypotension is present;
• there has been a recent stroke or heart attack;
• severe liver disease is present; or
• certain hereditary retinal conditions apply.

This list does not replace the complete patient information.

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Can I Take Viagra if I Have Heart Problems?

Erectile dysfunction medicines can have cardiovascular implications.

People with heart conditions should have their suitability assessed because sexual activity itself places additional demand on the cardiovascular system.

EMA specifically states that Viagra must not be used where sexual activity is inadvisable, such as in men with certain severe heart conditions.

Never conceal cardiovascular problems or medicines during a consultation.

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Can I Drink Alcohol With Viagra?

Alcohol can affect sexual performance and may make erectile dysfunction worse.

Large amounts of alcohol can also increase dizziness or blood-pressure-related effects.

Although modest alcohol consumption does not necessarily prevent sildenafil from working, limiting alcohol may improve both treatment reliability and erectile function.

Avoid using excessive alcohol as part of your preparation for sexual activity.

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Can Viagra Be Taken Every Day?

Viagra is normally taken as required, rather than automatically as a daily treatment.

The maximum recommended dosing frequency is once per day.

Do not take multiple doses within 24 hours.

If you require very frequent erectile dysfunction treatment, discuss your treatment strategy with an appropriate healthcare professional.

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Does Viagra Increase Sex Drive?

No.

Viagra treats the physical erectile response.

It does not directly increase libido or sexual desire.

A person can therefore have a normal erection response with sildenafil while still experiencing reduced desire caused by another issue.

Low libido and erectile dysfunction are related but different problems.

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Does Viagra Increase Testosterone?

No.

Sildenafil is not testosterone replacement therapy and is not designed to directly increase testosterone levels.

If erectile difficulties are accompanied by symptoms that could indicate a hormonal problem, a broader clinical assessment may be appropriate.

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Is Viagra an Aphrodisiac?

No.

Viagra does not create sexual attraction or desire.

It facilitates the physiological erectile response during sexual stimulation.

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Viagra vs Generic Sildenafil

Viagra and generic sildenafil contain the same active ingredient: sildenafil.

Generic sildenafil medicines approved in Europe must demonstrate appropriate comparability to the reference medicine, Viagra. EMA describes products such as Sildenafil Teva as generic versions of Viagra and notes that bioequivalent generics are expected to have the same benefits and risks as the reference medicine.

Viagra

• Original branded sildenafil treatment
• Contains sildenafil
• Available in 25mg, 50mg and 100mg strengths

Generic Sildenafil

• Contains the same active ingredient
• Usually less expensive
• May differ in manufacturer, appearance, packaging and inactive ingredients

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Viagra vs Spedra

Viagra and Spedra are both PDE5 inhibitors but contain different active ingredients.

Viagra

Contains sildenafil.

Spedra

Contains avanafil.

They differ in characteristics including:

• onset;
• dosing;
• interactions;
• individual response; and
• side-effect profiles.

One is not automatically better for every person.

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Viagra vs Vardenafil

Viagra contains sildenafil, while vardenafil is a separate PDE5 inhibitor used to treat erectile dysfunction.

Both enhance the natural erectile response during sexual stimulation but are not interchangeable on a milligram-for-milligram basis.

Treatment selection depends on individual circumstances and response.

View Vardenafil

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Viagra vs ED Pump Treatment

Not every erectile dysfunction option involves medication.

A vacuum erection device such as the VaxAid Deluxe ED Pump Kit uses a mechanical approach to help increase blood flow into the penis.

This may be considered by some men who:

• prefer a non-drug approach;
• cannot use a PDE5 inhibitor;
• experience unwanted medication effects; or
• require an alternative treatment strategy.