Sildenafil (Viagra): Uses, Dosage, and Safe Buying Tips
Sildenafil is the active drug in Viagra and a go-to option for erectile dysfunction (ED). It helps increase blood flow to the penis so you can get and keep an erection when sexually aroused. Many men get quick results, but a few common mistakes — wrong dose, mixing with nitrates, or buying fake pills — cause most problems. Here’s a clear, practical guide to using sildenafil safely.
Sildenafil comes as tablets for ED and a lower-dose version for pulmonary arterial hypertension (PAH). For ED, typical dosing is 25–100 mg taken about 30–60 minutes before sex. Most people start at 50 mg and adjust up or down based on effect and side effects. For PAH, the schedule and doses differ (usually lower, multiple times per day) — follow your prescriber exactly.
Common side effects are headache, flushing, stuffy nose, upset stomach, and temporary visual changes (blue tint or blurred vision). Serious signs that need urgent care are a painful erection lasting more than 4 hours (priapism), sudden vision loss, sudden hearing loss, chest pain, or fainting. If any of these happen, call emergency services right away.
Key drug interactions and safety rules
Never take sildenafil with nitrates (like nitroglycerin) — the combo can cause a dangerous drop in blood pressure. Be cautious with alpha-blockers for prostate issues or blood pressure; your doctor may adjust doses. Strong CYP3A4 inhibitors (like certain antifungals, HIV drugs, or grapefruit juice) can raise sildenafil levels and increase side effects. Tell your doctor all medicines and supplements you use before trying sildenafil.
How to buy sildenafil safely online
If you buy online, pick a licensed pharmacy that asks for a prescription. Red flags: no contact info, super-low prices, or sites that skip a prescription. Look for a verified seal (country-specific verification or pharmacy accreditation), an SSL connection (https://), and real customer reviews. Avoid pills marketed as “miracle” fixes. Counterfeit meds may contain wrong doses or harmful substances.
Practical tips: start with a low dose the first time you try it, avoid heavy meals and too much alcohol (they reduce effectiveness), and test timing — some men do better taking it 1–2 hours before sex. If you have heart disease, high blood pressure, or take multiple meds, get a checkup before using sildenafil. ED can signal underlying conditions like diabetes or blocked arteries, so a doctor visit may reveal treatable causes.
Want to compare options? Tadalafil (Cialis) lasts longer and can be taken daily at low dose; vardenafil is similar to sildenafil. If pills don’t work or cause problems, talk to your clinician about devices, injections, or referral to a specialist. If anything feels off, stop the drug and seek medical advice — safe use beats shortcuts every time.
