Discover how Sildenafil 100 mg, the active ingredient in Viagra®, improves erection by increasing blood flow to the penis. Its effect starts in 30 to 60 minutes and lasts up to 4 to 6 hours. Consult a doctor on Kano.care for safe and effective use.

How does Sildenafil 100 mg work and what is its duration of effect?

Dr. Sam Ward - Urologue et Andrologue

Medically reviewed by Dr. Sam Ward

Written by Anne-Sophie Laignel

Last updated 9/11/2024 - 6 min read

Sildenafil, more commonly known as Viagra, is one of the most widely used medications for treating erectile dysfunction (ED). The 100 mg form is often prescribed for moderate to severe cases of ED when lower doses are not sufficient. But how exactly does Sildenafil 100 mg work? And, more importantly, how long does its effect last? This article will explore in detail the mechanism of action of this medication, its duration of effect, and how it can improve the quality of life for men, and their partners, affected by erectile dysfunction.

What is Sildenafil?

Sildenafil belongs to a class of medications called phosphodiesterase type 5 (PDE-5) inhibitors. Its main role is to facilitate blood flow in the penis to allow an erection in response to sexual stimulation. To better understand this, let's see how an erection occurs naturally.

When a man is sexually stimulated, his body releases nitric oxide, a molecule that relaxes smooth muscles and dilates blood vessels in the penis. This allows an influx of blood, causing an erection. However, in men with erectile dysfunction, this natural response is disrupted. This is where Sildenafil comes into play: by inhibiting the PDE-5 enzyme, it helps to maintain high levels of nitric oxide, which prolongs the dilation of blood vessels and facilitates the achievement and maintenance of an erection.

How does Sildenafil 100 mg work in the body?

Sildenafil 100 mg is generally taken about one hour before any planned sexual activity. It starts to work after about 30 to 60 minutes, although this time can vary from one person to another depending on factors such as diet and overall health.

The medication does not cause an instant erection. In fact, it is only effective when there is sexual stimulation. If you are not aroused, there will be no erection, even after taking Sildenafil.

Duration of effect of Sildenafil 100 mg

One of the most common questions about Sildenafil is how long it lasts. After ingestion, the effects of Sildenafil 100 mg can last between 4 to 6 hours. This does not mean that you will have a continuous erection for this entire time, but rather that you will be able to achieve an erection with sexual stimulation during this period.

That said, the duration of the effect can vary depending on several factors, such as:

  • Individual metabolism: Men with a fast metabolism may see the effects of the drug wear off more quickly.
  • Alcohol and nutrition: A meal high in fats or excessive alcohol consumption can slow down the absorption of the medication and decrease its effectiveness.
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Side effects and precautions

Although Sildenafil is a widely used and generally well-tolerated medication, it can cause side effects. The most common ones include headaches, hot flashes, temporary visual disturbances (bluish vision), and indigestion. In rare cases, more serious side effects such as prolonged erection (priapism) may occur, especially in combination with illicit drugs. If this happens, immediate medical assistance is necessary.

It is essential to never take Sildenafil without a medical prescription and without consulting a doctor, especially if you have pre-existing medical conditions such as heart problems, hypertension, or if you are taking nitrate medications.

Why opt for Sildenafil 100 mg?

Sildenafil 100 mg is often the prescribed dose for men who have already tried lower doses without success. This higher dose may provide quicker and more effective results for those who need it. However, it is recommended to start with a lower dose, such as Sildenafil 50 mg, under a doctor's supervision, to determine the optimal dosage.

To get a prescription tailored to your needs, try the teleconsultation services of Kano, where you can get an online medical evaluation and receive a prescription directly without waiting. Don't wait any longer to regain a fulfilling sex life.

Sildenafil 100 mg vs other treatments for erectile dysfunction

There are several other treatments for erectile dysfunction, such as Tadalafil (Cialis), Vardenafil (Levitra), and penile injections. However, Sildenafil remains the most popular option due to its rapid effectiveness and relatively long duration of action. Compared to Tadalafil, for example, which can last up to 36 hours, Sildenafil is preferred for those who want a one-time solution with an action window of only a few hours.

When to consult a health professional?

It is important to consult a healthcare professional if you regularly experience difficulties in achieving or maintaining an erection. Erectile dysfunction can sometimes be a sign of an underlying medical condition, such as diabetes or heart disease. An accurate diagnosis is essential to choose the most appropriate treatment.

If you think that Sildenafil 100 mg might be a solution for you, consult our partner doctors at Kano. You can get an online consultation discreetly and receive your prescription quickly.

Sildenafil 100 mg is an effective and widely used treatment for erectile dysfunction. It helps men regain an active sex life by improving the ability to achieve and maintain an erection. With an effective duration of 4 to 6 hours, it offers a temporary but effective solution for men suffering from erectile dysfunction. However, it is crucial to consult a professional before starting any treatment.

Ready to take the first step towards a fulfilling sex life? Contact Kano now for an online consultation and get your prescription quickly, with complete discretion.

Consult an expert today to resolve your intimate health problems.
Dr. Sam Ward - Urologue et Andrologue

Révision médicale par le Dr. Sam Ward

Directeur médical, Urologue et Andrologue

Le Docteur Sam Ward, urologue et andrologue, dirige le service d'urologie à la Clinique Saint-Jean de Bruxelles depuis octobre 2024. Membre du Comité exécutif de la Chaire UNESCO Santé sexuelle & Droits humains et cofondateur de Kano.care, il est spécialise en santé masculine et médecine sexuelle.

En savoir plus sur notre équipe médicale

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Viagra® is a widely used medication for treating erectile dysfunction (ED), and it is often misunderstood regarding its actual effects on the penis. Its active ingredient, sildenafil, works by increasing blood flow to the penis during sexual stimulation. However, it is important to clarify that Viagra® does not increase penis size.

Incorporating physical activity into daily life: Small tips, big benefits

Physical activity plays a vital role in maintaining a fulfilling sex life. By improving blood circulation, reducing stress, increasing stamina, and strengthening pelvic muscles, exercise helps to optimize sexual performance. Even simple changes, such as regular muscle strengthening and cardiovascular exercises, can have a significant impact. This guide offers practical tips for incorporating exercise into daily life, promoting better sexual health. In case of persistent problems, it is important to consult health professionals through platforms like Kano.care for personalized support.

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Treatments for erectile dysfunction, such as Viagra®, Cialis®, Levitra®, and Spedra®, carry potential risks that vary depending on the patient's health condition. They may cause serious side effects, including cardiovascular issues, dangerous drug interactions, or prolonged erections (priapism), which require immediate medical attention. It is essential never to take these medications without the advice of a qualified healthcare professional. A thorough medical consultation is necessary to determine the appropriate treatment for each individual, taking into account medical history and contraindications. Additionally, it is crucial to ensure that the medications are obtained from reliable and authorized sources. Medications purchased outside legal channels or without a prescription may be counterfeit, ineffective, or even harmful to health. Always consult a doctor before using these treatments and obtain medications from a licensed pharmacy.

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