Sildenafil (brand name Viagra) is one of the most commonly used medicines for erectile dysfunction (ED). It helps increase blood flow to the penis so you can get and keep an erection when you're sexually aroused. It’s also prescribed in specific doses for pulmonary arterial hypertension. If you’re reading about sildenafil, you probably want straightforward, practical info — here it is.
Most men take sildenafil as a single tablet 30–60 minutes before sexual activity. It can work faster on an empty stomach; a heavy or fatty meal may slow it down. Typical starting doses are 25 mg, 50 mg, or 100 mg. Doctors often start at 50 mg and adjust up or down based on effect and side effects. Never take more than one dose in 24 hours.
If you have kidney or liver problems or are older, your doctor may recommend a lower dose. Always follow your prescriber's instructions. If sildenafil doesn’t work the first few times, don’t give up — your doctor may try a different dose or a different ED medicine.
Common side effects are headache, flushing, nasal congestion, indigestion, and mild changes in vision (blue tint or light sensitivity). Most side effects fade as the drug leaves your system. However, stop using sildenafil and seek immediate help if you get chest pain, sudden vision loss, or an erection lasting more than 4 hours (priapism). These are medical emergencies.
Do not take sildenafil if you use nitrates (for chest pain) — the combination can cause a dangerous drop in blood pressure. Be cautious if you’re on alpha-blockers, certain antifungals (like ketoconazole), macrolide antibiotics (like erythromycin), or HIV protease inhibitors — these can raise sildenafil levels and increase side effects. Avoid large amounts of alcohol and grapefruit juice; both can affect how sildenafil works.
Also tell your doctor about heart disease, low or high blood pressure, recent stroke, or severe liver or kidney disease. These conditions affect whether sildenafil is safe for you.
Thinking of buying sildenafil online? Use a reputable pharmacy. Look for a valid prescription requirement, clear contact info, and license or verification badges. Beware of sites that sell huge amounts without asking questions or offer unrealistic prices — they may ship counterfeit or unsafe pills. When in doubt, check with your doctor or a trusted pharmacy service.
Alternatives to sildenafil include tadalafil (longer-lasting) and vardenafil. Each drug has different timing and side effect profiles, so ask your provider which is best for your life and health.
Quick tips: start with the lowest effective dose, avoid nitrates, read labels for drug interactions, and buy from trusted pharmacies. If you have questions about dosing, side effects, or buying online, reach out to your healthcare provider — they can give advice based on your medical history.
© 2025. All rights reserved.
