What exactly is sildenafil?

Sildenafil is the active ingredient in the world-famous medication Viagra. Originally developed by pharmaceutical company Pfizer, Viagra was launched in 1998 as the first oral treatment for erection problems. It marked a revolution in the treatment of erectile dysfunction. Since Viagra’s patent expired in 2013, sildenafil has also been available as a generic medication. This means you can now get the same active ingredient without the Viagra brand name - often at a much lower price. Generic sildenafil is exactly the same medication with the same effectiveness and safety³, just without the brand premium.

How does sildenafil work in your body?

Sildenafil belongs to a group of medications called PDE5 inhibitors. To understand how it works, it helps to first understand what happens during an erection. When you become sexually aroused, your body produces a substance called cyclic guanosine monophosphate (cGMP). This substance causes the muscles in the blood vessels of the penis to relax, allowing more blood to flow into the spongy tissue of the penis - the corpora cavernosa. As these structures fill with blood, the penis becomes larger and firmer.

Normally, an enzyme called PDE5 breaks down cGMP, causing the erection to subside. With erection problems, this breakdown happens too quickly. Sildenafil inhibits the PDE5 enzyme, allowing cGMP to remain active longer. The result is improved blood flow and a firmer erection that lasts longer. Important to note: sildenafil only works with sexual arousal. It does not cause an automatic erection - you still need sexual stimulation. This makes it a natural and safe way to treat erection problems.

How quickly does sildenafil start working?

After taking sildenafil, it typically takes 30 to 60 minutes for the medication to start working. Peak effectiveness - the time when the medication works best - usually occurs between one and two hours after ingestion.

The exact onset time varies between individuals and depends on several factors:

• Your metabolism: faster metabolism may lead to faster onset

• Food intake: a heavy, fatty meal slows absorption

• Dosage: higher doses may work slightly faster

• Overall health and age

For best results, take sildenafil on an empty stomach or after a light meal. A heavy, fatty meal can delay its effect by 30–60 minutes. Plan to take sildenafil about one hour before sexual activity.

How long does sildenafil last?

Sildenafil remains active in the body for approximately 4 to 6 hours. This does not mean you will have an erection for that entire time - which would be uncomfortable and potentially dangerous. Instead, it means that during this period, it will be easier to get an erection when you are sexually aroused. After about 4 hours, the effect begins to wear off as half of the active substance has left your body. After 6 hours, the effect is usually gone. This makes sildenafil a practical choice for planned sexual activity. If you prefer more flexibility and spontaneity, tadalafil may be a better alternative. Tadalafil works for up to 36 hours, allowing greater freedom in timing.

What dosages are available and which one is right for you?

At Menkind, sildenafil is available in 50 mg and 100 mg dosages (generic sildenafil as well as branded Viagra). The standard starting dose is 50 mg. This dose is effective for most men and causes relatively few side effects.

If 50 mg is not effective enough, your doctor may increase the dose to 100 mg. Clinical research shows that approximately 82% of users experience significant improvement¹. More broadly, 94% of men report improved sexual performance and satisfaction after using sildenafil². It’s important to try the medication several times before judging its effectiveness - the first attempt may be less effective due to nervousness.

What are the side effects of sildenafil?

Sildenafil is clinically proven to be safe and is used by millions of men worldwide². As with any medication, side effects can occur, but they are usually mild and temporary.

The most common side effects are:

• Headache (most common)

• Flushing (red face)

• Nasal congestion

• Indigestion or heartburn

• Mild dizziness

• Temporary changes in color vision (rare)⁴

These side effects usually resolve on their own as the medication wears off. They are most noticeable around peak effect (1–2 hours after intake) and then gradually subside.

Serious side effects are very rare, but contact a doctor immediately if you experience:

• Chest pain

• An erection lasting longer than 4 hours (priapism)

• Sudden changes in vision or hearing

Interestingly, several studies suggest that sildenafil may also have a positive effect on premature ejaculation and overall sexual satisfaction⁵.

When should you not use sildenafil?

Although sildenafil is safe for most men, there are situations where it should not be used.

Do NOT use sildenafil if you:

Use nitrates (medications for heart conditions such as nitroglycerin)

• Have recently had a heart attack or stroke

• Have severe heart or liver disease

• Have very low blood pressure

• Have certain rare eye conditions

Always use caution and consult a doctor if you:

• Take other medications (some may interact with sildenafil)

• Have cardiovascular disease

• Have a history of priapism

At Menkind, your medical situation is carefully reviewed by a registered doctor before sildenafil is prescribed. This is done via a secure online questionnaire and, if needed, direct contact with the doctor.

How to use sildenafil effectively

For best results, it’s important to use sildenafil correctly. Key tips include:

• Timing: Take sildenafil about one hour before planned sexual activity.

• Food: Preferably on an empty stomach or after a light meal; fatty meals delay onset.

• Frequency: Use sildenafil no more than once every 24 hours. More is not better and increases side-effect risk.

• Alcohol: Limit alcohol intake. Excessive alcohol can reduce effectiveness and increase side effects such as dizziness.

• Patience: Give the medication time. Some men experience the best results after several uses, once anxiety decreases.

• Sexual stimulation: Remember that sexual arousal is required - sildenafil does not work automatically.

If sildenafil does not work well enough, discuss this with your doctor. A different dosage or an alternative such as tadalafil may be more suitable for you⁶.

Conclusion

Sildenafil is a proven, safe, and effective treatment for erection problems. It works by improving blood flow to the penis and helps approximately 82 of users¹. It begins working within 30–60 minutes and remains effective for 4–6 hours.

Side effects are usually mild and temporary, with headache, flushing, and nasal congestion being the most common. By using sildenafil correctly - at the right time, in the right dose, and not too frequently - you maximize effectiveness and minimize side effects. There is only a small and limited group of men who are not allowed to use this medicine because of their medical history.

At Menkind, you can discreetly request an online treatment plan with sildenafil from a registered doctor. Once approved, your medication is delivered quickly and discreetly to your home. You can choose between branded Viagra or generic sildenafil, both available in 50 mg and 100 mg, either as a one-time order or via subscription.

References 

1. Carson, C. C., et al. (2002). The efficacy of sildenafil citrate (Viagra) in clinical populations: an update. International Journal of Impotence Research, 14(Suppl 1), S109-S115. https://pubmed.ncbi.nlm.nih.gov/12414330/

2. McMurray, J. G., et al. (2007). Long-term safety and effectiveness of sildenafil citrate in men with erectile dysfunction. Therapeutics and Clinical Risk Management, 3(6). https://pubmed.ncbi.nlm.nih.gov/18516312/

3. Jackson, G., et al. (2005). Past, present, and future: a 7-year update of Viagra (sildenafil citrate). International Journal of Clinical Practice, 59(6), 680-691. https://pubmed.ncbi.nlm.nih.gov/15924597/

4. Apotheek.nl. Sildenafil bijsluiter. https://www.apotheek.nl/medicijnen/sildenafil

5. Wang, W. F., et al. (2007). Can sildenafil treat primary premature ejaculation? A prospective clinical study. International Journal of Urology, 14(4), 331-335. https://pubmed.ncbi.nlm.nih.gov/17470165/

6. Pfizer. Erectiestoornissen: feiten en fabels. https://www.pfizer.nl