viagra
| Product dosage: 100mg | |||
|---|---|---|---|
| Package (num) | Per pill | Price | Buy |
| 10 | $4.51 | $45.14 (0%) | 🛒 Add to cart |
| 20 | $2.76 | $90.27 $55.17 (39%) | 🛒 Add to cart |
| 30 | $2.17 | $135.41 $65.20 (52%) | 🛒 Add to cart |
| 60 | $1.50 | $270.81 $90.27 (67%) | 🛒 Add to cart |
| 90 | $1.45 | $406.22 $130.39 (68%) | 🛒 Add to cart |
| 120 | $1.34 | $541.63 $160.48 (70%) | 🛒 Add to cart |
| 180 | $1.23 | $812.44 $220.66 (73%) | 🛒 Add to cart |
| 270 | $1.11 | $1218.66 $300.90 (75%) | 🛒 Add to cart |
| 360 | $1.00
Best per pill | $1624.88 $361.08 (78%) | 🛒 Add to cart |
| Product dosage: 25mg | |||
|---|---|---|---|
| Package (num) | Per pill | Price | Buy |
| 20 | $2.01 | $40.12 (0%) | 🛒 Add to cart |
| 30 | $1.50 | $60.18 $45.14 (25%) | 🛒 Add to cart |
| 60 | $0.92 | $120.36 $55.17 (54%) | 🛒 Add to cart |
| 90 | $0.67 | $180.54 $60.18 (67%) | 🛒 Add to cart |
| 120 | $0.59 | $240.72 $70.21 (71%) | 🛒 Add to cart |
| 180 | $0.45 | $361.08 $80.24 (78%) | 🛒 Add to cart |
| 270 | $0.32 | $541.63 $85.26 (84%) | 🛒 Add to cart |
| 360 | $0.26
Best per pill | $722.17 $95.29 (87%) | 🛒 Add to cart |
| Product dosage: 50mg | |||
|---|---|---|---|
| Package (num) | Per pill | Price | Buy |
| 10 | $4.01 | $40.12 (0%) | 🛒 Add to cart |
| 20 | $2.51 | $80.24 $50.15 (38%) | 🛒 Add to cart |
| 30 | $1.84 | $120.36 $55.17 (54%) | 🛒 Add to cart |
| 60 | $1.34 | $240.72 $80.24 (67%) | 🛒 Add to cart |
| 90 | $1.11 | $361.08 $100.30 (72%) | 🛒 Add to cart |
| 120 | $1.00 | $481.45 $120.36 (75%) | 🛒 Add to cart |
| 180 | $0.84 | $722.17 $150.45 (79%) | 🛒 Add to cart |
| 270 | $0.76 | $1083.25 $205.62 (81%) | 🛒 Add to cart |
| 360 | $0.70
Best per pill | $1444.34 $250.75 (83%) | 🛒 Add to cart |
Synonyms | |||
Similar products
Let me walk you through what we’ve learned about sildenafil citrate - the active component in Viagra - over the past two decades. When Pfizer initially developed this compound for angina, nobody anticipated it would revolutionize sexual medicine. I remember sitting in a urology conference in 1998 when the first erectile dysfunction data was presented - the room was absolutely electric. We knew we were witnessing a paradigm shift.
Viagra: Effective Erectile Dysfunction Treatment - Evidence-Based Review
1. Introduction: What is Viagra? Its Role in Modern Medicine
Viagra contains sildenafil citrate, a phosphodiesterase type 5 (PDE5) inhibitor that fundamentally changed how we approach erectile dysfunction. Before its 1998 FDA approval, treatment options were pretty limited - injections, vacuum devices, implants. The introduction of an oral medication that could reliably produce erections was nothing short of revolutionary in sexual medicine.
What’s fascinating is how accidental this discovery was. The cardiovascular team at Pfizer was studying sildenafil for hypertension and angina when male participants started reporting an unexpected side effect - improved erections. The rest, as they say, is history. Now, over two decades later, we’ve prescribed millions of doses and have a much clearer picture of how it works in diverse patient populations.
2. Key Components and Bioavailability Viagra
The active pharmaceutical ingredient is straightforward - sildenafil citrate. But what many clinicians don’t appreciate is the formulation science behind why the 25mg, 50mg, and 100mg tablets work so consistently.
The bioavailability sits around 40% - not fantastic by modern standards, but the crystalline structure and excipients in the branded formulation ensure pretty reliable absorption. Peak plasma concentrations hit about 60 minutes post-administration in fasted state, though I’ve seen patients respond in as little as 30 minutes. Food, particularly high-fat meals, can delay absorption by up to an hour and reduce Cmax by nearly 30% - something I always emphasize to patients.
The tablet uses microcrystalline cellulose and calcium hydrogen phosphate as fillers, but the real magic is in the manufacturing process that creates consistent dissolution profiles batch after batch.
3. Mechanism of Action Viagra: Scientific Substantiation
Here’s where it gets interesting clinically. Sildenafil doesn’t cause erections - it enables them. The mechanism is elegantly simple: during sexual stimulation, nitric oxide release activates guanylate cyclase, increasing cyclic GMP levels. This causes smooth muscle relaxation in the corpus cavernosum, allowing blood flow for erection.
PDE5 normally breaks down cGMP, terminating the signal. Sildenafil competitively inhibits PDE5, preserving cGMP and prolonging the erectile response. What many patients don’t realize is that sexual stimulation is still required - the medication simply amplifies the natural physiological response.
We’ve found this mechanism has interesting implications beyond erectile function. The same PDE5 enzyme exists in pulmonary vasculature, which is why sildenafil got approved for pulmonary arterial hypertension under the name Revatio.
4. Indications for Use: What is Viagra Effective For?
Viagra for Erectile Dysfunction
This remains the primary indication. In our practice, we see success rates around 70-80% for organic ED, though psychological factors can influence response. The key is proper patient selection and dosing.
Viagra for Pulmonary Arterial Hypertension
At lower, more frequent dosing (20mg TID), sildenafil improves exercise capacity and hemodynamics in PAH patients. The vascular effects are quite pronounced.
Off-label Uses Worth Mentioning
We’ve had some success with Raynaud’s phenomenon and high-altitude pulmonary edema, though the evidence is less robust. There’s ongoing research into cognitive benefits and even antidepressant augmentation.
5. Instructions for Use: Dosage and Course of Administration
Dosing is more art than science sometimes. The standard starting dose is 50mg taken approximately 30-60 minutes before sexual activity, but I individualize heavily based on age, comorbidities, and medication history.
| Clinical Scenario | Recommended Dose | Timing | Special Instructions |
|---|---|---|---|
| First-time user, otherwise healthy | 50mg | 30-60 min before activity | Take on empty stomach for fastest onset |
| Elderly (>65) or hepatic impairment | 25mg | 45-60 min before | Monitor for dizziness, hypotension |
| Inadequate response | 100mg | 60 min before | Maximum recommended dose |
| With alpha-blockers | 25mg | 4+ hours after alpha-blocker | Contraindicated with certain alpha-blockers |
The maximum dosing frequency is once daily. I’ve had patients try to take multiple doses in 24 hours - the headaches and flushing become pretty intolerable.
6. Contraindications and Drug Interactions Viagra
This is where clinical judgment really matters. Absolute contraindications include concurrent nitrate therapy - the hypotension risk is very real. I had a patient once who used nitroglycerin paste and took Viagra - his BP dropped to 70/40 and we had to manage him in the ER overnight.
Relative contraindications include recent MI, unstable angina, hypotension, and severe hepatic impairment. The drug interaction profile is extensive - alpha-blockers require careful timing, CYP3A4 inhibitors like ketoconazole can dramatically increase levels.
The side effect profile is generally mild - headache (16%), flushing (10%), dyspepsia (7%) from PDE6 inhibition in the gut. The blue vision thing is real but uncommon - maybe 3% of patients notice it.
7. Clinical Studies and Evidence Base Viagra
The data is overwhelmingly positive. The original 1998 NEJM study showed 69% of attempts successful with 100mg versus 22% with placebo. What’s more impressive is the long-term data - we’ve followed patients on continuous therapy for over 10 years with maintained efficacy.
More recent studies have looked at specific populations - diabetics respond well though sometimes need higher doses, post-prostatectomy patients have about 50% response with nerve-sparing techniques. The psychological benefits are substantial too - improved self-esteem, relationship satisfaction.
The real-world evidence from post-marketing surveillance involving millions of patients confirms the safety profile. The cardiovascular risk is minimal in properly selected patients.
8. Comparing Viagra with Similar Products and Choosing a Quality Product
The PDE5 inhibitor class has expanded significantly. Cialis offers longer duration, Levitra has somewhat faster onset in some studies, Stendra might have less visual side effects. But Viagra remains the gold standard for reliability.
Generic sildenafil became available in 2017, and the bioequivalence data is solid. The cost difference is substantial - often 80% less than branded. The main issue I’ve seen with generics is consistency between manufacturers - some patients respond differently to different generic versions.
Counterfeit products are a real concern. I had a patient buying online who got tablets containing only talc and blue food coloring. The packaging looked perfect but the medication was useless.
9. Frequently Asked Questions (FAQ) about Viagra
What is the recommended course of Viagra to achieve results?
Most patients respond within the first few doses. If no response after 4-6 attempts at maximum dose, we consider alternative diagnoses or treatments.
Can Viagra be combined with blood pressure medications?
Generally yes, with careful monitoring. The exception is nitrates - that combination is dangerous.
How long does Viagra stay in your system?
The half-life is about 4 hours, so mostly cleared in 24 hours, though some effects might linger.
Is Viagra safe for long-term use?
We have 20+ years of data showing excellent long-term safety in appropriate patients.
10. Conclusion: Validity of Viagra Use in Clinical Practice
The risk-benefit profile remains strongly positive for appropriate candidates. After all these years, it’s still my first-line oral therapy for most erectile dysfunction cases.
I’ll never forget Mr. Henderson, 58-year-old accountant with diabetes-induced ED for 3 years. He’d tried everything - injections terrified him, the vacuum device felt “medical and unnatural.” When I prescribed 50mg Viagra, he returned two weeks later with tears in his eyes - his first successful intercourse in years. But what struck me was his wife’s comment: “You gave me my husband back.”
Then there was the learning curve - like the 42-year-old who took 100mg right after Thanksgiving dinner and called me panicked because “nothing happened.” The high-fat meal had delayed absorption by nearly two hours. We adjusted timing and he’s been fine since.
The cardiovascular team initially fought the sexual dysfunction indication - they worried it would trivialize their “serious” cardiovascular drug. There were heated debates about whether we were medicalizing normal aging. But the quality of life data won them over eventually.
What surprised me most was the psychological impact. We had one patient, early 60s with mild ED, whose marriage was suffering from the sexual frustration. After starting Viagra, his depression scores improved dramatically even though his ED was relatively mild. The restored intimacy and confidence had ripple effects throughout his life.
We’ve followed some patients for over 15 years now on continuous therapy. The efficacy holds up remarkably well, though some diabetic patients need dose escalation over time. The safety profile has been excellent - no increased cardiovascular events in our properly screened population.
The most common complaint isn’t lack of efficacy - it’s the cost. Even with generics available, many patients struggle with the expense. We’ve developed relationships with several pharmacies that offer discount programs, and we sample when we can.
Looking back, I’m still amazed at how one accidental discovery transformed so many lives and created an entirely new field of sexual medicine. The blue pill started a revolution that’s still evolving today.