Pfizer Viagra

Viagra — Complete Guide: Uses, How It Works, Dosage & Side Effects

Viagra is a well‑known prescription medication developed by Pfizer that contains Sildenafil. It’s primarily used to treat erectile dysfunction (ED) — the inability to achieve or maintain an erection sufficient for sexual intercourse.

What Is Viagra?

Viagra is an oral phosphodiesterase‑5 (PDE5) inhibitor that helps improve blood flow to the penis when a man is sexually stimulated. It does not automatically cause an erection — sexual arousal is still required. The drug is available in 25 mg, 50 mg and 100 mg tablet strengths.

How Viagra Works

During sexual arousal, nitric oxide is released in penile tissue, which leads to increased levels of cGMP — a molecule that relaxes smooth muscle and allows the blood vessels in the penis to open. Viagra blocks the enzyme PDE5, which normally breaks down cGMP. By preventing this breakdown, sildenafil allows cGMP to build up and improve blood flow, helping to produce and maintain an erection.

Onset & Duration

• Viagra generally starts to work 30 to 60 minutes after taking the tablet.

• Its effects can last up to 4 hours, though peak effects often occur between 1–2.5 hours after ingestion.

Recommended Dosage

Standard dosing recommendations for erectile dysfunction:

• 25 mg: starting dose for older adults or those with certain health conditions

• 50 mg: typical starting dose, taken about 1 hour before sexual activity

• 100 mg: maximum recommended dose if lower doses aren’t effective

Viagra should not be taken more than once in 24 hours.

Important Safety Warnings

Do Not Use If:

• You’re taking nitrate medications (e.g., nitroglycerin), as dangerous drops in blood pressure can occur.

• You’re allergic to sildenafil or any component of the tablet.

Health Conditions to Discuss With Your Doctor

• Heart problems or recent heart attack/stroke

• Low blood pressure

• Severe liver or kidney impairment

• Retinal disorders (vision issues)

• Use of certain blood pressure medicines or alpha blockers

Common Side Effects

Viagra is generally well tolerated, but side effects may include:

• Headache

• Flushing

• Indigestion / stomach discomfort

• Nasal congestion

• Dizziness

• Vision changes (e.g., color tinting)

Less common but serious risks include prolonged erection (lasting > 4 hours), sudden vision or hearing loss, and significant blood pressure drops — all requiring immediate medical help.

Final Summary

Viagra is a clinically proven treatment for erectile dysfunction that works by increasing blood flow to the penis in response to sexual stimulation. Taken orally 30–60 minutes before sex, it can help men achieve and maintain an erection.

However, it must be used responsibly under medical supervision due to potential interactions and side effects. Always follow your healthcare provider’s guidance and never use prescription medicines without proper oversight.