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What is sildenafil?

Sildenafil better known as viagra is the active pharmaceutical ingredient used to treat erectile dysfunction (ED) in adult men.
It was the first effective oral treatment for ED and is the active substance behind brand-name products (such as Viagra) as well as many generic versions.

📌 Important: sildenafil does not increase sexual desire. It works only when there is sexual stimulation.

How does it work?

Sildenafil belongs to a group of medicines called PDE-5 inhibitors (phosphodiesterase type 5 inhibitors).

During sexual stimulation:

• The body releases nitric oxide (NO)

• Levels of cyclic GMP (cGMP) increase

• Blood vessels in the penis relax and widen

• More blood flows in → an erection occurs

🔹 Sildenafil blocks the PDE-5 enzyme, preventing cGMP from breaking down too quickly
🔹 Result: stronger and longer-lasting erections

How is it used?

💊 Administration

• Oral tablet

• Taken with water

• Before sexual activity

⏱️ When to take it

• Usually 30–60 minutes before sex

• In some people it may take up to 2 hours

• Duration of effect: 4–6 hours

⚠️ Heavy or high-fat meals can delay or reduce the effect.

📏 Typical dosage

• 25 mg → low dose (older adults or sensitive users)

• 50 mg → standard and most common dose

• 100 mg → maximum usual dose

🚫 Do not take more than one dose per day

The appropriate dose depends on age, health status, and other medications.

⚠️ Most common side effects

Usually mild and temporary:

• Headache

• Facial flushing

• Nasal congestion

• Indigestion or heartburn

• Mild dizziness

• Mild visual changes (bluish vision, increased brightness)

🚨 An erection lasting more than 4 hours (priapism) is a medical emergency.

🚫 Who should NOT use sildenafil?

Do not use sildenafil if:

• You take nitrates (e.g., nitroglycerin, isosorbide)
  ⚠️ Can cause a dangerous drop in blood pressure

• You have:

  • Severe or uncontrolled heart disease

  • Recent heart attack or stroke

  • Severe low blood pressure

• You are allergic to sildenafil

⚠️ Always consult a doctor if:

• You take blood-pressure medication

• You have diabetes

• You have liver or kidney disease

❌ Common myths

❌ “It causes automatic erections” → FALSE
❌ “It increases penis size” → FALSE
❌ “It is addictive” → FALSE

✔️ It simply enhances the body’s natural erectile response to sexual stimulation.

Quick summary

• 💊 Oral medication for erectile dysfunction

• ⏱️ Take 30–60 minutes before sex

• ⏳ Effect lasts 4–6 hours

• 🔁 Improves erection quality, not desire

• ⚠️ Never combine with nitrates

If you want, I can also explain:

• differences between sildenafil, tadalafil, and vardenafil

• which option lasts longer

• safe use in people with diabetes

• or what to do if sildenafil doesn’t work the first time