Vilitra, Vardenafil

1. Introduction to Vilitra (Vardenafil)

Overview of Vilitra as a Phosphodiesterase-5 (PDE5) Inhibitor

Vilitra is a prescription medication containing the active ingredient Vardenafil, a selective phosphodiesterase type 5 (PDE5) inhibitor. It is primarily used to enhance erectile function by increasing blood flow to the penile tissue, enabling a firm and sustained erection during sexual stimulation.

Approval History and Regulatory Status

Vardenafil, the active compound in Vilitra, received FDA approval for the treatment of erectile dysfunction in 2003. While Vilitra itself may be marketed as a generic or international formulation, it complies with the therapeutic standards established for PDE5 inhibitors in multiple regulatory jurisdictions.

Comparison with Other ED Medications (Sildenafil, Tadalafil)

Vilitra is often compared to Sildenafil (Viagra) and Tadalafil (Cialis). While all three are PDE5 inhibitors, Vilitra is known for its rapid onset of action and relatively shorter duration:

• Faster onset than Tadalafil
• More selective inhibition of PDE5 than Sildenafil
• Shorter half-life, which may reduce long-term side effect risk

Marketed Strengths and Formulations (Vilitra 10mg, 20mg, 40mg, 60mg)

Vilitra is available in several oral strengths to accommodate individual response and tolerance:

• Vilitra 10mg – low-dose starter option
• Vilitra 20mg – standard recommended dose
• Vilitra 40mg and 60mg – higher doses for refractory cases under medical supervision

2. Medical and Off-Label Uses of Vilitra

2.1 FDA-Approved Use

Vilitra is approved for the treatment of erectile dysfunction (ED) in adult males, defined as the consistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance.

2.2 Off-Label Uses

Though not officially sanctioned by regulatory agencies, Vilitra is occasionally employed off-label in various clinical scenarios:

• Pulmonary arterial hypertension (PAH): May improve vascular relaxation in pulmonary arteries.
• Raynaud’s phenomenon: Used experimentally to enhance peripheral circulation.
• Sexual performance anxiety: Utilized to alleviate psychogenic erectile dysfunction.
• Premature ejaculation: Investigated as a potential adjunct to delay ejaculation.
• Benign prostatic hyperplasia (BPH): May support erectile function when coexisting with BPH symptoms.

3. Mechanism of Action: How Vilitra (Vardenafil) Works

PDE5 Enzyme Inhibition and cGMP Elevation

Vilitra inhibits the PDE5 enzyme, responsible for breaking down cyclic guanosine monophosphate (cGMP) in the corpus cavernosum. By preserving cGMP levels, the drug facilitates vasodilation and erectile tissue engorgement.

Enhancement of Nitric Oxide-Mediated Vasodilation

Nitric oxide, released during sexual stimulation, activates guanylate cyclase and raises cGMP concentrations. Vilitra amplifies this pathway, thereby enhancing erectile quality and duration.

Specificity for Penile Corpus Cavernosum Smooth Muscle

The drug’s selectivity for PDE5, which is predominantly found in penile tissue, ensures targeted action with reduced systemic effects.

Onset and Duration of Action Compared to Other PDE5 Inhibitors

• Onset: Typically within 25–60 minutes
• Duration: Effective up to 5 hours
• Shorter duration than Tadalafil but longer than Avanafil

4. Composition and Available Formulations

Active Pharmaceutical Ingredient: Vardenafil Hydrochloride

Vilitra contains Vardenafil HCl as the active substance, which is structurally similar to Sildenafil but exhibits greater PDE5 selectivity.

Inactive Ingredients and Excipients

Common excipients include:

• Lactose monohydrate
• Microcrystalline cellulose
• Colorants and film-coating agents

Tablet Forms: Film-Coated and Orally Disintegrating

Vilitra is marketed in traditional film-coated tablets and orally disintegrating forms for patients with swallowing difficulties.

Bioavailability and Pharmacokinetic Profile

• Bioavailability: Approximately 15%
• Peak plasma levels: Achieved within 1 hour
• Half-life: Approximately 4–5 hours

5. Dosage and Administration Guidelines

5.1 Standard Adult Dosing for Erectile Dysfunction

• Starting dose: 10mg taken orally 25–60 minutes before sexual activity
• Maintenance: May be increased to 20mg or decreased to 5mg based on tolerability
• Maximum dose: Once per day

Timing in Relation to Sexual Activity and Meals

Vilitra can be taken with or without food, though high-fat meals may delay absorption and onset. Sexual stimulation is required for efficacy.

5.2 Adjustments Based on Medical Conditions

• Hepatic impairment: Initiate with 5mg; avoid in severe liver dysfunction
• Renal impairment: Use with caution; insufficient data in severe renal disease
• Interacting medications: Reduce dose when used with potent CYP3A4 inhibitors

6. Administration Considerations in Special Populations

6.1 Elderly Patients

Older adults may exhibit increased sensitivity due to age-related pharmacodynamic changes. Initiate with lower doses and monitor blood pressure response.

6.2 Pregnant and Nursing Women

Vilitra is not indicated for use in women. No adequate data exist on teratogenic effects or excretion into human milk. Use during pregnancy and lactation is contraindicated.

6.3 Pediatric and Adolescent Use

The safety and efficacy of Vilitra in individuals under 18 years of age have not been established. Pediatric use is not recommended and may carry risks of unknown long-term consequences.

7. Common and Serious Side Effects of Vilitra

7.1 Frequently Reported Side Effects

Most side effects are transient and mild to moderate in intensity:

• Headache
• Flushing
• Nasal congestion
• Dyspepsia (indigestion)
• Dizziness
• Back or muscle pain

7.2 Less Common but Serious Adverse Effects

Some adverse reactions require immediate discontinuation and medical intervention:

• Sudden hearing loss: Rare but documented, possibly sensorineural in origin
• Visual disturbances: Including non-arteritic anterior ischemic optic neuropathy (NAION)
• Priapism: An erection lasting longer than 4 hours, which can lead to irreversible damage if untreated

8. Important Precautions and Careful Administration Guidelines

Cardiovascular Assessment Before Initiation

Before prescribing Vilitra, a thorough cardiovascular evaluation is essential. Since sexual activity itself exerts a cardiac workload, patients with a history of cardiovascular disease—including angina, congestive heart failure, or arrhythmias—should be carefully assessed to determine whether they can safely engage in such activity.

Risk of Hypotension in Combination with Nitrates or Alpha-Blockers

The concurrent use of Vilitra with nitrates (such as nitroglycerin) or guanylate cyclase stimulators is contraindicated due to the potential for profound and life-threatening hypotension. Similarly, combining Vilitra with alpha-blockers (e.g., tamsulosin, doxazosin) may lead to symptomatic hypotension, especially if not appropriately spaced in administration timing.

Use in Patients with Anatomical Penile Deformities (e.g., Peyronie’s Disease)

Patients with anatomical abnormalities of the penis—such as angulation, cavernosal fibrosis, or Peyronie’s disease—should use Vilitra with caution. These conditions increase the risk of priapism, a prolonged and potentially harmful erection.

Risk of Retinal Disorders or Visual Impairment

There is a rare but significant risk of non-arteritic anterior ischemic optic neuropathy (NAION), a sudden loss of vision that may be irreversible. Patients with a history of retinal disorders or those with underlying risk factors such as hypertension, diabetes, or hyperlipidemia should be monitored closely.

9. Contraindications for Vilitra Use

• Known hypersensitivity: Patients with a known allergy to Vardenafil or any component of the tablet should not take Vilitra.
• Concurrent use with nitrates: Strongly contraindicated due to the risk of severe hypotension.
• Guanylate cyclase stimulators: Including drugs like riociguat, due to additive blood pressure-lowering effects.
• Severe hepatic or renal impairment: In patients with end-stage liver or kidney disease, Vardenafil metabolism and clearance are significantly impaired, heightening toxicity risks.
• Recent myocardial infarction or stroke: Use is contraindicated within the last 6 months of such events due to cardiac strain risk.
• Prolonged QT interval: Vardenafil may prolong the QT interval, increasing the risk of torsades de pointes, particularly when used with other QT-prolonging drugs.

10. Drug and Food Interactions with Vilitra

10.1 Pharmacokinetic Drug Interactions

• CYP3A4 inhibitors: Strong inhibitors like ketoconazole, itraconazole, ritonavir, and indinavir may significantly elevate plasma levels of Vardenafil. Dose adjustments or alternative therapies should be considered.
• Nitrates and nitric oxide donors: The vasodilatory effects of both drugs can synergistically cause dangerous hypotension.
• Alpha-blockers and antihypertensives: Concurrent use may lead to symptomatic hypotension. Patients should be stabilized on alpha-blocker therapy before starting Vilitra and monitored for postural effects.

10.2 Dietary and Substance Interactions

• Grapefruit juice: Potent inhibitor of CYP3A4; may delay metabolism and increase plasma concentration of Vardenafil, resulting in exaggerated effects or side effects.
• Alcohol: Excessive consumption may augment the vasodilatory effects of Vilitra, leading to dizziness, fainting, or hypotension.

11. Overdose Risk and Emergency Management

Symptoms of Overdose

Signs of a Vilitra overdose may include:

• Severe hypotension
• Prolonged and painful erection (priapism)
• Visual disturbances or temporary vision loss
• Nausea, chest pain, or arrhythmias

Recommended Supportive and Symptomatic Treatment

Management involves supportive measures:

• Cardiac monitoring and stabilization
• Symptomatic management of hypotension with IV fluids and vasopressors
• Emergency intervention for priapism to avoid permanent tissue damage

No Specific Antidote Available

There is no specific reversal agent for Vardenafil overdose. Hemodialysis is unlikely to be effective due to high protein binding.

12. Storage and Handling of Vilitra Tablets

• Storage temperature: Keep at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C and 30°C.
• Humidity: Store in a dry environment, away from excessive moisture.
• Safety: Keep the tablets out of reach of children and pets to prevent accidental ingestion.
• Disposal: Unused or expired tablets should be disposed of according to local pharmaceutical waste guidelines—never flush down the toilet or throw in household trash.

13. Safe Handling and Dispensing Precautions

• Protective handling: While not hazardous to touch, pharmacists may wear gloves to prevent contamination of other substances or skin irritation in sensitive individuals.
• Do not crush or split: Unless scored or approved by a healthcare provider, tablets should not be altered, as this may affect drug absorption or efficacy.
• Secure packaging: Always store Vilitra in its original blister or container to protect from light, humidity, and unintended usage.