Penegra (Sildenafil Citrate)

Introduction

Penegra contains the active compound Sildenafil Citrate, a phosphodiesterase-5 (PDE5) inhibitor formulated as an oral tablet. It is marketed in strengths of 25 mg, 50 mg, and 100 mg. The medication belongs to the class of selective PDE5 inhibitors and is primarily used to treat erectile dysfunction (ED) and pulmonary arterial hypertension (PAH). Sildenafil was first approved by the U.S. Food and Drug Administration (FDA) in 1998 for ED (under the brand name Viagra) and later, in a lower dose formulation, for PAH (under the brand name Revatio). Penegra offers the same therapeutic benefits at a lower cost, providing a generic alternative for patients who need reliable, evidence-based treatment.

What is Penegra?

Penegra is a generic formulation of Sildenafil Citrate supplied as film-coated tablets. The drug was originally discovered by researchers at Pfizer while investigating treatments for angina, and its utility for erectile dysfunction was identified during clinical trials. While the exact manufacturer of Penegra may vary by market, the product is produced under GMP-compliant conditions and distributed through licensed pharmaceutical wholesalers.

Penegra is the generic version of well-known medications, containing the active compound Sildenafil Citrate. Our online pharmacy provides this generic alternative as a cost-effective treatment option.

How Penegra Works

Sildenafil Citrate selectively blocks the enzyme phosphodiesterase type 5 (PDE5). In the penis, PDE5 breaks down cyclic guanosine monophosphate (cGMP), a messenger that mediates smooth-muscle relaxation. By inhibiting PDE5, Penegra preserves cGMP levels, allowing nitric oxide-stimulated vasodilation of the corpus cavernosum. This results in increased blood flow and an erection sufficient for sexual activity, provided that sexual stimulation occurs.

In the pulmonary vasculature, PDE5 is also present in smooth muscle cells. Inhibition of PDE5 leads to elevated cGMP, causing pulmonary arterial dilation and a reduction in pulmonary arterial pressure. The drug’s onset of action is typically observed within 30-60 minutes after oral intake, with peak plasma concentrations reached in about 1 hour. The therapeutic effect may last 4-6 hours, while the elimination half-life is approximately 3-5 hours, allowing clearance primarily via hepatic metabolism (CYP3A4) and renal excretion.

Conditions Treated with Penegra

These indications are supported by large-scale, randomized, placebo-controlled trials (e.g., the VISION and SUPER studies for ED, and the PHIRST and START trials for PAH). Regulatory agencies such as the FDA, EMA, and Health Canada have granted formal approval for these uses.

Off-Label and Investigational Uses of Penegra

• Raynaud’s Phenomenon - Small clinical series have reported reduced frequency of digital vasospasm after low-dose sildenafil, suggesting improved peripheral blood flow.
• High-Altitude Pulmonary Edema (HAPE) - Prophylactic administration in mountaineers has been investigated for its ability to lower pulmonary artery pressure at altitude.
• Heart Failure with Reduced Ejection Fraction (HFrEF) - Some phase II studies show modest improvements in cardiac output when combined with standard heart-failure therapy.

These off-label applications are not approved by major regulatory bodies and should be considered only under strict medical supervision. Evidence is limited, safety profiles in these populations remain incompletely defined, and benefit-risk assessments must be individualized.

Is Penegra the Right Medication for You?

Penegra is suitable for adult men (≥ 18 years) who have a confirmed diagnosis of erectile dysfunction and for patients diagnosed with pulmonary arterial hypertension. It is especially useful when a rapid onset of action is desired, or when cost constraints make branded products prohibitive.

Contraindications include:

• Concurrent use of nitrates (e.g., nitroglycerin) or nitric oxide donors.
• Severe uncontrolled hypertension (systolic > 180 mmHg or diastolic > 100 mmHg).
• Known hypersensitivity to sildenafil or any tablet excipients.
• Recent (≤ 24 h) use of potent CYP3A4 inhibitors such as ketoconazole or itraconazole, which can markedly increase sildenafil exposure.

Patients with significant cardiovascular disease, recent myocardial infarction, or those on alpha-adrenergic blockers should discuss suitability with a qualified healthcare professional before initiating therapy.

Risks, Side Effects, and Interactions

Common

• Headache
• Flushing
• Dyspepsia (indigestion)
• Nasal congestion
• Visual disturbances (e.g., blue-tinted vision)

These events are generally mild, transient, and resolve without medical intervention.

Rare

• Priapism (prolonged erection > 4 hours)
• Sudden hearing loss
• Acute myocardial ischemia in patients with underlying coronary artery disease
• Skin rash or urticaria

Prompt evaluation is advised if any of these occur.

Serious

• Severe hypotension, especially when combined with nitrates.
• Non-arteritic anterior ischemic optic neuropathy (NAION).
• Life-threatening allergic reactions (anaphylaxis).

Immediate emergency care is required for serious events.

Drug-Drug Interactions

• Nitrates (nitroglycerin, isosorbide dinitrate) - additive vasodilation → fatal hypotension.
• Alpha-blockers - may increase risk of orthostatic hypotension.
• CYP3A4 inhibitors (e.g., ketoconazole, ritonavir) - raise sildenafil plasma levels → higher adverse-event risk.
• CYP3A4 inducers (e.g., rifampin, carbamazepine) - lower plasma concentrations → reduced efficacy.

Food and Alcohol

• High-fat meals can delay onset by 30-60 minutes.
• Moderate alcohol consumption may enhance hypotensive effects; excessive intake should be avoided.

Use: Dosing, Missed Dose, Overdose

Standard Dosing for Erectile Dysfunction

• Start with 50 mg taken as needed about 1 hour before sexual activity.
• Dose may be adjusted to 25 mg or 100 mg based on efficacy and tolerability.
• Do not exceed one tablet per 24-hour period.

Standard Dosing for Pulmonary Arterial Hypertension (off-label use only)

• 20 mg three times daily with food, spaced evenly throughout the day.

Missed Dose

• If a dose is forgotten and the scheduled time is still ≥ 4 hours away, take the tablet.
• If the next dose is within 4 hours, skip the missed dose and continue the regular schedule.
• Do not double-dose to compensate for a missed tablet.

Overdose

• Symptoms may include profound hypotension, syncope, prolonged erection, or visual changes.
• Seek immediate medical attention; supportive care (intravenous fluids, vasopressors) is the mainstay of treatment.

Practical Precautions

• Take with or without food; avoid large, fatty meals shortly before dosing to ensure timely onset.
• Limit alcohol intake, as it can increase dizziness and lower blood pressure.
• Do not operate heavy machinery or drive if you experience visual blur, dizziness, or hypotension.

FAQ

• Can I travel internationally with Penegra? • Yes, the tablet is permitted for personal use in most countries, provided you carry a copy of the prescription or a legitimate medical statement. Check the destination’s customs regulations beforehand to avoid confiscation.

• How should Penegra be stored in hot climates? • Keep the tablets in a dry place at temperatures below 30 °C (86 °F). If you expect prolonged exposure to heat, store the bottle in a insulated container or a climate-controlled cabinet.

• What does the Penegra tablet look like? • The tablets are round, film-coated, and bear distinctive imprint codes that differ by strength (e.g., “25 mg - P25”, “50 mg - P50”, “100 mg - P100”). The color varies from light blue (25 mg) to dark blue (100 mg).

• Which inactive ingredients are present in Penegra? • Common excipients include microcrystalline cellulose, croscarmellose sodium, magnesium stearate, and a small amount of titanium dioxide for coating. These components are standard across most sildenafil generic formulations.

• Does Penegra show up on standard drug tests? • Routine workplace drug screens (e.g., immunoassay for opioids, cannabinoids, amphetamines) do not detect sildenafil. Specialized testing would be required, but such testing is rarely performed outside clinical research.

• Is Penegra safe for people with liver disease? • Because sildenafil is metabolized principally by the liver, moderate hepatic impairment may increase drug exposure. Dose reduction (e.g., starting at 25 mg) is advisable, and patients with severe liver dysfunction should be evaluated before use.

• How long does it take for Penegra to work after a meal? • When taken with a high-fat meal, the time to onset may be delayed by up to 60 minutes compared with fasting conditions. A light meal or taking the tablet on an empty stomach generally results in faster absorption.

• Can I take Penegra with alcohol? • Light to moderate alcohol consumption does not usually interfere with efficacy, but excessive drinking can worsen hypotension and dizziness. It is prudent to limit alcohol to a single standard drink when using the medication.

• What is the history of Sildenafil development? • Sildenafil was originally synthesized in 1989 as a potential anti-anginal agent. Early clinical trials revealed a pronounced effect on penile erection, leading to its rapid repurposing for ED. The drug received FDA approval in 1998 and has since become a standard treatment for both ED and PAH.

• How does Penegra compare with older vasodilators like nitroglycerin? • Nitroglycerin works by releasing nitric oxide directly, causing rapid but short-lasting vasodilation, and is primarily used for angina. Penegra, via PDE5 inhibition, augments the nitric-oxide pathway downstream, offering a more targeted effect on the corpus cavernosum and pulmonary vasculature with a longer duration of action.

Glossary

Phosphodiesterase type 5 (PDE5)

An enzyme that degrades cyclic guanosine monophosphate (cGMP), limiting smooth-muscle relaxation in the penis and pulmonary arteries.

cGMP (Cyclic Guanosine Monophosphate)

A intracellular messenger that promotes vasodilation by relaxing smooth-muscle cells; increased levels lead to improved blood flow.

Pulmonary Arterial Hypertension (PAH)

A progressive condition characterized by high blood pressure in the arteries supplying the lungs, leading to right-heart strain and reduced exercise capacity.

Contraindication

A specific situation or condition where a medication should not be used because the risks outweigh any potential benefit.

Buying Penegra from Our Online Pharmacy

Penegra can be obtained safely and discreetly from our online pharmacy. We source the medication exclusively from licensed, GMP-certified manufacturers, ensuring that each tablet meets stringent quality standards. Our pricing structure is designed to reflect near-manufacturer costs, providing a cost-effective alternative to branded products.

Delivery is handled through secure, discreet packaging, with express options typically arriving within 7 days and standard airmail shipments in approximately 3 weeks. Because we operate as a pharmacy-broker service, we partner with reputable overseas pharmacies that hold the necessary regulatory authorizations, allowing us to offer medications that may be unavailable or prohibitively expensive in local markets.

Our commitment to privacy means your personal data is protected throughout the transaction, and no identifying information appears on the shipping label. Whether you have limited access to traditional pharmacies or are seeking a more affordable generic solution, our online pharmacy offers a reliable pathway to obtain Penegra with confidence.

Disclaimer

The information presented about Penegra is intended for general educational purposes and does not substitute professional medical advice. Treatment decisions, including considerations of off-label use, should be made under the direct supervision of a qualified healthcare provider. Readers are presumed to be responsible adults capable of making informed health choices. Our online pharmacy supplies Penegra to individuals who may encounter restricted availability through conventional pharmacies or who are looking for cost-effective generic alternatives. Always discuss any medication changes with a healthcare professional before initiating, adjusting, or stopping therapy.