Sildenafil — Uses, Dosing, Side Effects, and Smart Buying Tips

Sildenafil is the medicine behind Viagra and many generics. It helps improve blood flow to treat erectile dysfunction and is also used for pulmonary arterial hypertension. If you want quick, practical facts about how to use it safely and where to buy trusted versions, this page covers the essentials.

How sildenafil works and common doses

Sildenafil relaxes blood vessels in the penis and lungs by blocking an enzyme called PDE5. That makes it easier to get and keep an erection when you are sexually stimulated. Common oral doses for erectile dysfunction are 25 mg, 50 mg, and 100 mg taken about 30–60 minutes before sex. For pulmonary hypertension, doses and schedules differ and must be prescribed by a specialist.

Safety and side effects

The most common side effects are headache, flushing, upset stomach, nasal congestion, and dizziness. Serious reactions are rare but can include sudden vision or hearing loss and priapism — an erection lasting longer than four hours that needs immediate care. Never take sildenafil with nitrates or nitric-oxide donors (often prescribed for chest pain) — the combination can dangerously lower blood pressure. Tell your doctor about heart disease, low blood pressure, stroke, liver or kidney problems, and medications like alpha-blockers and certain antifungals or antibiotics that interact with sildenafil.

Older adults usually start at a lower dose. If you have reduced kidney or liver function, your doctor will adjust dosing. Avoid heavy alcohol with sildenafil — drinking a lot can reduce effectiveness and raise side effects.

There are generic sildenafil tablets and branded options, plus combination or herbal products that claim to help with erectile problems. Be cautious: many so-called natural pills hide prescription ingredients or wrong doses.

Smart buying and usage tips

Always get a prescription for sildenafil. Legitimate online pharmacies require a prescription and display contact info, pharmacist access, clear labeling. Look for verified reviews, a physical address, secure checkout. Check pill imprints, packaging quality, and expiration dates when your order arrives. If the price looks too low or the site ships without a prescription, it’s risky.

Start with the lowest effective dose and try it once or twice to see how you react. Take it on an empty stomach or avoid very fatty meals for faster action. If sildenafil does not work, don’t increase the dose on your own — talk to your clinician about alternatives like tadalafil or counseling about underlying causes.

If you get chest pain, faint, have sudden vision loss, or an erection lasting over four hours, seek emergency care. For ongoing questions—side effects, interactions, or safety—talk to your doctor or pharmacist before buying or changing doses.

Many articles on this site cover buying sildenafil online, generic options, and comparisons with other ED drugs. Read reviews, compare prices, and ask a pharmacist about interactions. If you are unsure, schedule a quick telehealth consult — getting the right dose and safe product is worth a minute on the phone and saves money too today.