What ВИАСИЛ Treats: Main Uses and Benefits

ВИАСИЛ (Sildenafil) is commonly used to provide symptomatic support across therapeutic domains involving localized physiological function and systemic imbalance, and is considered relevant in both these therapeutic areas.

It is generally used in conditions involving erectile dysfunction (ED) and the management of Pulmonary Arterial Hypertension (PAH). The medicine helps address groups of symptoms related to physical discomfort and creates noticeable physiological strain. It is commonly applied in clinical settings that involve acute or unstable symptom patterns, or when chronic conditions require supportive relief to manage systemic imbalance.

“The primary benefit is that it supports the patient during difficult episodes by easing distress and assists with maintaining functional stability.”

The medication may assist with maintaining functional stability when symptoms interfere with daily comfort. In patients with PAH, it contributes to easing the overall symptom load by addressing symptoms related to heightened physiological activity, such as shortness of breath and fatigue, which may support general well-being during symptomatic phases.

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Quick Fact: Supportive Role in Functional Domains ВИАСИЛ is applied in conditions that produce significant symptomatic burden, assisting with maintaining functional stability in two key areas: supporting the management of impaired erectile response and improving exercise tolerance in chronic pulmonary conditions.

Regulatory References

1. NIH MedlinePlus overview of Sildenafil

Who can and cannot use ВИАСИЛ?

Eligibility for Sildenafil (ВИАСИЛ) use is strictly determined by official regulatory criteria, which define populations who are absolutely prohibited (contraindicated) and those whose use must be restricted.

Populations for whom use is Contraindicated

Absolute prohibition applies to patients using organic nitrates or nitric oxide donors in any form, or guanylate cyclase (GC) stimulators (e.g., riociguat). These combinations are forbidden due to the risk of severe, life-threatening hypotension. Sildenafil is also contraindicated in patients with a known hypersensitivity, a history of non-arteritic anterior ischaemic optic neuropathy (NAION), recent stroke or myocardial infarction (within 6 months), unstable angina, severe cardiac failure, or severe hepatic impairment.

Restricted and Age-Related Eligibility

Use is established for adult males (for ED) and adults (for PAH). For the ED indication, the medicine is not indicated for individuals under 18 years of age. Cautious use is required in patients with conditions predisposing to priapism, anatomical penile deformations, severe renal impairment, or mild to moderate hepatic impairment. Sildenafil is not indicated for use in women, including during pregnancy or lactation.

Interactions with other medicines and products

This section outlines officially documented interaction patterns for Sildenafil based on government regulatory information.

Contraindicated Combinations

Co-administration of Sildenafil with Organic Nitrates, Nitric Oxide Donors, and Guanylate Cyclase Stimulators (e.g., Riociguat) is formally contraindicated. This restriction is due to a severe pharmacodynamic interaction resulting in an additive, potentially fatal blood pressure lowering effect.

Pharmacokinetic and Exposure Interactions

Sildenafil is cleared primarily by the hepatic enzyme Cytochrome P450 3A4 (CYP3A4). Substances that inhibit CYP3A4 (e.g., Ritonavir, Ketoconazole) cause a significant increase in Sildenafil plasma exposure (AUC and Cmax) by reducing its clearance. Conversely, CYP3A4 inducers (e.g., Bosentan) may reduce Sildenafil plasma levels.

Interaction-Related Restrictions and Constraints

Constraint	Official Regulatory Requirement
Timing Restriction (Nitrates)	Administration of nitrates must be separated by 24 hours from Sildenafil use.
Dose Restriction (CYP3A4 Inhibitors)	A maximum dose of 25 mg in a 48-hour period is imposed when co-administering with potent CYP3A4 inhibitors (e.g., Ritonavir).
Other Medicines	Co-administration with Alpha-blockers or other antihypertensive agents may result in additive blood pressure lowering effects.
Food Interaction	A high-fat meal reduces the rate of Sildenafil absorption, delaying the time to maximum concentration (Tmax) and reducing Cmax.
Population Note	Sildenafil clearance is reduced in patients with hepatic impairment, resulting in increased systemic exposure.

Targeted Inhibition of the PDE5 Enzyme

The core mechanism involves the selective, competitive inhibition of the Phosphodiesterase type 5 (PDE5) enzyme. This enzyme is naturally tasked with breaking down cyclic Guanosine Monophosphate (cGMP), a critical signaling molecule. By blocking this degradation, the drug ensures cGMP levels rapidly accumulate within the smooth muscle cells where PDE5 is active.

Amplification of the Nitric Oxide Signaling Cascade

Sildenafil operates as a modulator within the body's natural Nitric Oxide (NO)-cGMP signaling cascade. This mechanism is NO-dependent, meaning the drug can only augment the existing physiological signal and cannot induce the effect spontaneously. The resultant prolonged elevation of cGMP mediates a cascade of events leading to vascular smooth muscle relaxation and subsequent localized vasodilation .

Mechanism-Driven Increase in Regional Blood Flow

The physiological consequence of sustained smooth muscle relaxation is the widening of the targeted blood vessels, which leads to an increased and flow-dependent regional blood perfusion. The high selectivity for PDE5 focuses this action predominantly in specific vascular beds, though minor cross-reactivity with the retinal PDE6 enzyme can lead to transient changes in the visual cascade.

How to Use ВИАСИЛ: General Administration Guidelines

ВИАСИЛ (Sildenafil) is administered via the oral route, available as tablets or a powder for oral suspension. The medicine is also supplied as an intravenous (IV) injection for temporary use in supervised settings, typically when the oral route is not clinically feasible for the Pulmonary Arterial Hypertension (PAH) regimen.

Dosing Regimens and Frequency

The required dosing regimen is differentiated by the therapeutic context. For as-needed use, the standard starting dose is 50 mg, with adjustments permitted within a range of 25 mg to 100 mg; administration must not exceed once per day. For chronic maintenance therapy, the standard oral dose is 20 mg, administered three times a day at intervals of 4 to 6 hours.

Administration Context and Adjustments

The dose for as-needed use is typically taken approximately one hour prior to the desired activity. The medicine may be taken with or without food; however, ingestion with a high-fat meal can result in a delayed onset of activity. A reduced starting dose of 25 mg may be applied for specific populations, including older adults (aged ≥ 65 years) and patients with severe renal or hepatic impairment. Additionally, the oral suspension form requires reconstitution and thorough shaking before use to ensure accurate measurement.

Research Evidence for Use in Erectile Dysfunction (ED)

Research for ED focused on short-term randomized, double-blind, placebo-controlled clinical trials (RCTs). These trials evaluated outcomes like the ability to achieve and maintain an erection, using validated patient questionnaires. Study populations included adult men with various causes for ED, including those with conditions like diabetes.

Study Types and Outcomes Examined for ED

Key research explored short-term symptom changes, typically over 12 weeks. Evidence from longer open-label extension studies was used to observe responses over extended follow-up periods.

Research Evidence for Use in Pulmonary Arterial Hypertension (PAH)

Sildenafil was studied for PAH using RCTs applied in research contexts involving this severe, chronic condition. Researchers examined outcomes related to exercise capacity (6-minute walk distance) and monitored the time to clinical worsening, a composite measure of critical events. Data show patterns related to changes in these functional and clinical event outcomes over the observed time intervals.

Study Types and Outcomes Examined for PAH

Initial controlled trials covered 12 to 16 weeks, examining changes in physiological markers and symptom patterns in populations primarily classified as WHO Functional Class II or III.

Long-Term Studies and Follow-up Durations

Research explored outcomes through open-label extension studies for both indications, with observed follow-up durations extending up to a few years. These longer efforts contribute to understanding symptom patterns over time but lack the strict comparative structure of initial RCTs.

Evidence in Special Populations

Research was studied for special populations in PAH, specifically examining children and adolescents. Evidence is limited and certainty remains low regarding specific dose-related outcomes in pediatric populations, leading to regulatory discussions. Adult ED studies were observed in subgroups with comorbidities like diabetes.

What is Still Uncertain About ВИАСИЛ Research

Long-term outcomes are not fully established through continuous, controlled clinical trials. For the pediatric PAH population, data are still emerging regarding optimal long-term usage. Results apply only to the populations studied, meaning individual outcomes may vary.

Common questions about ВИАСИЛ (FAQ)

Q: How long does the effect of a single dose of ВИАСИЛ typically last?

Official information indicates that the active ingredient, sildenafil, has a typical terminal half-life of 3 to 5 hours. The therapeutic effects are generally observed and sustained for at least three hours after a single dose.

Q: Can ВИАСИЛ be taken with food, or should it be on an empty stomach?

According to the official product information, the medicine may be taken with or without food. However, it is noted that taking it alongside a high-fat meal may lead to a delay in the onset of its activity in the body.

Q: What are some of the most serious but rare side effects of ВИАСИЛ?

Regulatory documents list certain rare but serious adverse reactions, including a prolonged erection lasting over four hours (priapism), sudden decrease or loss of vision, and sudden decrease or loss of hearing. These are listed as serious events that regulatory documents require to be reported immediately to a healthcare professional.

Q: What kind of medicines are known to interact with ВИАСИЛ?

The medicine is known to interact with several classes of drugs. These include organic nitrates and nitric oxide donors, guanylate cyclase stimulators, certain antifungals and HIV protease inhibitors (which affect drug clearance), and alpha-blockers used for blood pressure.

Q: Is there a generic version of ВИАСИЛ available?

Yes, the active ingredient in this medicine is sildenafil. Official health agencies confirm that sildenafil is widely available in generic form.

Q: Can ВИАСИЛ be used by someone with kidney problems?

Official product information notes that the use of this medicine requires caution in patients with severe kidney impairment. For this specific population, official guidelines stipulate that a reduced starting dose is considered.

Q: Can ВИАСИЛ be used by someone with liver problems?

Official product information states that the medicine is contraindicated (absolutely prohibited) in patients with severe hepatic impairment (severe liver problems). For mild to moderate liver impairment, a reduced starting dose may be necessary due to how the drug is cleared from the body.

Q: What is the chemical structure of the active component in ВИАСИЛ?

The active component is sildenafil, which is a chemically synthesized substance. According to the National Institutes of Health, it is classified as a pyrazolo[4,3-d]pyrimidin-7-one derivative.

Q: Does ВИАСИЛ have different strengths available?

Yes, the medicine is available in several strengths, depending on the indication (intended use). This includes 25 mg, 50 mg, and 100 mg tablets, with 20 mg tablets being the standard dose for chronic maintenance therapy.

Q: Can taking ВИАСИЛ affect your blood pressure?

Sildenafil is known to have vasodilatory properties, which means it causes blood vessels to widen. This action typically results in a mild and transient decrease in blood pressure.

Q: Does drinking alcohol affect how ВИАСИЛ works?

Official health sources advise that consuming excessive amounts of alcohol may intensify the blood pressure-lowering effects of this class of medication. This may also temporarily reduce the ability to achieve an erection.

Q: Are there specific age limits for who can use ВИАСИЛ?

For its use in treating erectile dysfunction, the medicine is not indicated for individuals under 18 years of age. For other approved conditions (like pulmonary hypertension), the use and dosing for these patients is managed by a specialist.

Q: Can ВИАСИЛ be used by women?

For the treatment of erectile dysfunction, the medicine is not indicated for use in women. This prohibition includes those who are pregnant or breastfeeding.

Q: How is ВИАСИЛ different from the drug that treats pulmonary hypertension?

The active ingredient, sildenafil, is the same substance used to treat both conditions. However, it is marketed under different brand names and is available in different formulations and strengths specific to each medical indication, as approved by regulatory agencies.

Q: Can ВИАСИЛ be split or crushed to take a smaller dose?

Official product information does not provide instructions for splitting or crushing the oral tablets. The medicine is manufactured in pre-measured strengths, and an oral suspension (liquid) is available for specific dosing needs.

Q: Why do some people need a higher dose of ВИАСИЛ than others?

Official prescribing information states that the dose may be adjusted based on the effectiveness and tolerability experienced by the patient. Doses are also reduced for older adults and for patients with severe renal or hepatic impairment.

Q: Is there any risk associated with taking ВИАСИЛ regularly for years?

Long-term use of the active ingredient was observed in studies extending up to a few years. Regulatory safety documents note that these long-term exposure observations did not show an excess of serious cardiovascular side effects.

Q: Does ВИАСИЛ affect fertility or hormone levels?

Official health information does not describe any clear evidence to suggest that the active ingredient reduces fertility in men or women or significantly alters hormone levels.

Q: Can a patient get ВИАСИЛ through an online pharmacy?

This medicine is classified as a prescription-only medication. Therefore, obtaining it through any dispensing service, including online pharmacies, is subject to the specific national regulatory requirements for prescription drugs.

Q: Is it necessary to take ВИАСИЛ at the same time every day?

For as-needed use, the medicine is taken approximately one hour before the desired activity and is taken as needed (not more than once per day). It does not require administration at the same fixed time every day, though chronic maintenance therapy may require specific timing.

Q: Does ВИАСИЛ interact with herbal supplements?

Official health sources state the importance of informing a healthcare professional about all herbal remedies or supplements being used. This is because these products are not tested in the same way as prescription medicines and may pose an unknown risk of interaction with sildenafil.

Q: How long after taking ВИАСИЛ is it considered safe to drive or operate machinery?

Due to the potential for the medicine to cause temporary visual disturbances or dizziness, regulatory warnings state that individuals must observe their reaction to the medicine before driving or operating machinery.

Q: Does ВИАСИЛ have different names in other countries?

Yes, the active ingredient, sildenafil, is marketed globally under multiple different brand names and generic labels. The specific brand name used depends on the country and the medical condition being treated.

Q: Are there different forms of ВИАСИЛ, like a tablet versus a chewable?

Official documents describe the medicine as being available in the form of oral tablets and a powder for oral suspension (liquid). Additionally, some regulatory bodies have approved chewable tablet forms of the active ingredient.

Q: Does ВИАСИЛ require any special monitoring or regular blood tests?

Official prescribing information does not generally mandate regular blood tests for all users. However, close monitoring may be specifically required for patients who are also taking other blood pressure-lowering drugs.

Q: How is the safety profile of ВИАСИЛ described in regulatory documents?

Regulatory agencies have generally concluded that the benefit of the medicine outweighs the identified risks when it is used strictly according to the approved indications and official guidelines.

Q: Are there any post-market safety concerns reported for ВИАСИЛ?

Post-marketing surveillance has reported rare, serious adverse events that occurred in association with use. These reports include cardiovascular events, prolonged erection (priapism), and sudden visual or hearing loss.

The storage and disposal of Sildenafil (ВИАСИЛ) must be handled strictly according to the conditions mandated by official regulatory documentation to maintain product stability and ensure safety.

Official Storage Requirements

Item	Regulatory Requirement
Temperature	Store tablets at a temperature not exceeding 30 C.
Protection	Must be kept in the original package, protected from moisture and light.
Packaging	The container must be kept tightly closed.
Child Safety	Must be kept out of the sight and reach of children.

Stability and Disposal

For the oral suspension form, the product is stable for 60 days after reconstitution and must not be frozen. Unused or expired medication must be disposed of in accordance with local pharmaceutical waste requirements; regulatory labeling explicitly states the product must not be discarded via wastewater or household trash.