Generic Viagra (Sildenafil Citrate )

Introduction

Viagra contains the active ingredient sildenafil citrate, a phosphodiesterase-5 (PDE-5) inhibitor approved for the treatment of erectile dysfunction (ED) in adult males. It is supplied in oral tablet form with strengths of 25 mg, 50 mg, 100 mg, 120 mg, 130 mg, 150 mg and 200 mg. The medication belongs to the class of selective PDE-5 inhibitors and is also approved for pulmonary arterial hypertension (PAH) under the brand name Revatio. Approved uses focus on improving erectile response and reducing pulmonary vascular resistance. Off-label investigations have examined its role in conditions such as Raynaud’s phenomenon and certain forms of heart failure, though these applications have not received regulatory approval.

What is Viagra?

Viagra is a medication whose therapeutic effect derives from the compound sildenafil citrate. It was originally developed by Pfizer in the early s and received FDA approval for erectile dysfunction in 1998. The drug is marketed under the brand name Viagra for ED and under the brand name Revatio for PAH. Our online pharmacy provides this generic alternative as a cost-effective treatment option for patients who meet the approved indications.

How Viagra Works

Sildenafil citrate selectively inhibits the enzyme phosphodiesterase-5, which degrades cyclic guanosine monophosphate (cG c). In the corpus cavernosum of the penis, sexual stimulation releases nitric oxide, increasing cG c levels. By preventing cG c breakdown, sildenafil prolongs smooth-muscle relaxation, allowing arterial inflow to fill the erectile tissue. The typical onset of action is 30-60 minutes after oral intake, and therapeutic effects may last 4-6 hours. The drug is metabolized primarily by hepatic CYP3A4 and CYP2C9; the elimination half-life is approximately 4 hours.

Conditions Treated with Viagra

• Erectile Dysfunction (ED). Sildenafil enhances erectile response by augmenting the nitric oxide-cG c pathway, leading to sufficient blood flow for satisfactory sexual performance. Randomized controlled trials have demonstrated significant improvement in International Index of Erectile Function (IIEF) scores compared with placebo.
• Pulmonary Arterial Hypertension (PAH). Under the brand Revatio, sildenafil reduces pulmonary vascular resistance, improves exercise capacity, and delays clinical worsening in adults with PAH. The FDA approval is based on the results of the SUPER and PDE-5 studies showing improved six-minute walk distance.

Off-Label and Investigational Uses of Viagra

• Raynaud’s phenomenon and digital ischemia. Small clinical studies suggest that sildenafil may improve peripheral blood flow in severe Raynaud’s attacks, but evidence remains limited.
• Heart failure with reduced ejection fraction. Early-phase trials have explored sildenafil’s potential to improve ventricular remodeling, yet no large-scale outcomes have been published.
• High-altitude pulmonary edema. Investigational protocols have examined sildenafil for prophylaxis against altitude-related pulmonary hypertension.

These uses are not approved by the FDA or EMA. Patients considering off-label therapy should do so only under direct supervision of a qualified healthcare provider, as safety and efficacy have not been formally established.

Is Viagra the Right Medication for You?

Viagra is appropriate for adult males diagnosed with erectile dysfunction who have a demonstrated need for pharmacologic enhancement of erectile response. It is also suitable for patients with pulmonary arterial hypertension when prescribed under the Revatio label. The medication is particularly effective when taken on an empty stomach, as high-fat meals can delay absorption. Contraindications include concomitant use of nitrates, severe hypotension, recent myocardial infarction, severe liver impairment, and known hypersensitivity to sildenafil or any tablet component. Patients with uncontrolled hypertension, significant retinal disorders, or certain rare genetic disorders (e.g., retinitis pigmentosa) should avoid sildenafil.

Risks, Side Effects, and Interactions

Common

• Headache
• Flushing
• Dyspepsia (indigestion)
• Nasal congestion
• Visual disturbances (blue-tint vision)

Rare

• Priapism (prolonged erection lasting >4 hours)
• Sudden hearing loss
• Mild hypotension

Serious

• Cardiovascular events (myocardial infarction, stroke) in patients with pre-existing risk factors
• Severe hypotension when combined with nitrates or alpha-blockers
• Vision loss due to non-arteritic ischemic optic neuropathy (NAION)

Drug-Drug Interactions

• Nitrates (e.g., nitroglycerin) → marked hypotension, contraindicated.
• Alpha-blockers (e.g., doxazosin) → additive blood pressure lowering; dose titration required.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin) → increase sildenafil plasma levels; dose reduction may be needed.
• CYP3A4 inducers (e.g., rifampin) → reduce efficacy; consider higher dose if tolerated.

Drug-Food Interactions

• High-fat meals can delay absorption, extending time to onset.
• Excessive alcohol may potentiate hypotensive effects and impair erectile response.

Use: Dosing, Missed Dose, Overdose

Standard dosing for erectile dysfunction starts at 50 mg taken approximately one hour before sexual activity. The dose may be adjusted to 25 mg or 100 mg based on efficacy and tolerability; higher strengths (120-200 mg) are occasionally prescribed in specialized cases but are not first-line. For pulmonary arterial hypertension, the approved regimen is 20 mg three times daily.

If a dose is missed, the tablet should be taken as soon as the patient remembers, provided there is at least 4 hours before the next scheduled dose; otherwise, skip the missed dose and resume the regular schedule. Taking two doses within a short interval increases the risk of hypotension and should be avoided.

In the event of an overdose, patients may experience severe hypotension, visual changes, or priapism. Immediate medical attention is advised; treatment is supportive, focusing on blood pressure stabilization and monitoring for cardiac complications.

FAQ

• **Can I travel with Viagra?   Yes. Keep tablets in the original packaging with a copy of the prescription, if required, and store them in a cool, dry place. TSA regulations permit personal medication in carry-on bags.

• **Does grapefruit affect sildenafil?   Grapefruit juice inhibits CYP3A4, potentially increasing sildenafil plasma concentrations. Limit grapefruit consumption to avoid enhanced side effects.

• **What does the tablet look like?   Sildenafil tablets are typically round, bicolored (blue-white, pink-white, or green-white) with the dosage imprint (e.g., “50” for 50 mg). Inactive ingredients may include lactose, maize starch, and magnesium stearate.

• **Are there regional formulation differences?   Yes. Some markets use film-coated tablets, while others employ immediate-release formulations. Regulatory agencies require bioequivalence, but excipient profiles can vary.

• **Is sildenafil detectable on drug tests?   Standard employment drug panels do not test for sildenafil. Specialized testing can detect the drug, but this is rarely performed outside forensic contexts.

• **Can I take sildenafil if I have high blood pressure?   Patients with controlled hypertension may use sildenafil safely, but uncontrolled blood pressure is a contraindication. Blood pressure should be monitored before initiating therapy.

• **How does sildenafil differ from other ED drugs?   Sildenafil has a relatively rapid onset (30-60 min) and a duration of 4-6 hours. Tadalafil (Cialis) has a longer half-life (≈17 h), allowing daily dosing, while vardenafil (Levitra) has a similar onset but different side-effect profile.

• **What was the original purpose of sildenafil’s development?   Sildenafil was initially investigated for angina pectoris because of its vasodilatory properties. During clinical trials, a pronounced effect on penile erection was observed, leading to its repurposing for ED.

• **Can I use sildenafil with herbal supplements?   Certain supplements, such as L-arginine or yohimbine, may potentiate vasodilatory effects. Discuss any supplement use with a healthcare professional to avoid additive hypotension.

• **What storage conditions are recommended?   Store tablets at 20-25 °C (68-77 °F) in a dry environment, protected from light and moisture. Do not refrigerate or freeze.

Glossary

Phosphodiesterase-5 (PDE-5) Inhibitor

A drug class that blocks the PDE-5 enzyme, preventing breakdown of cG c and promoting smooth-muscle relaxation in vascular tissues.

cG c (Cyclic Guanosine Monophosphate)

A second messenger that mediates vasodilation; increased levels lead to relaxation of smooth muscle in the corpus cavernosum and pulmonary arteries.

Priapism

An erection lasting longer than four hours without sexual stimulation, requiring prompt medical evaluation to prevent tissue damage.

Buying Viagra from Our Online pharmacy

Patients seeking a reliable, cost-effective source of sildenafil citrate can obtain the medication from our online pharmacy. We source tablets from licensed, vetted suppliers that meet international quality standards, ensuring that each product matches the purity and potency required by regulatory agencies.

• Affordability: Prices are close to manufacturer-direct rates, reducing the financial burden for patients without insurance coverage.
• Verified Quality: All shipments are packed under strict Good Manufacturing Practice (GMP) oversight, with batch verification performed before dispatch.
• Discrete Delivery: Orders are shipped in unmarked packaging, with optional express service (delivery within 7 days) or standard airmail (approximately 3 weeks).
• Global Access: Our pharmacy broker service works with overseas licensed pharmacies, extending access to patients in regions where local availability is limited.

By partnering with our online pharmacy, patients gain a secure, private, and affordable pathway to obtain sildenafil citrate when traditional pharmacy channels are inaccessible or costly.

Disclaimer

The information presented about Viagra serves educational purposes only and does not replace professional medical advice. Treatment decisions, including those concerning off-label applications, must be made under the guidance of a qualified healthcare provider. Readers are presumed to be mature adults capable of informed health decisions. Our online pharmacy offers access to Viagra for individuals who may encounter limited availability through conventional pharmacies or insurance formularies, or who are seeking affordable generic alternatives. Consultation with a physician is essential before initiating, modifying, or discontinuing any medication.