Sidegra is manufactured by Thailand's state-run Government Pharmaceutical Organization (GPO) and launched in 2012 as an affordable alternative to brand-name Viagra. Priced at approximately 80 US cents per pill (compared to $8-10 for Viagra), it was created to combat counterfeit production and increase access to legitimate erectile dysfunction treatment.
What is Sildenafil? Sildenafil citrate is a phosphodiesterase type-5 (PDE-5) inhibitor that works by relaxing blood vessels in the penis, increasing blood flow during sexual stimulation. Originally developed by Pfizer and FDA-approved in 1998, sildenafil revolutionized erectile dysfunction treatment with its oral, on-demand dosing.
The verdict? Highly effective, well-studied pharmaceutical with strong clinical evidence, but requires medical supervision. Before sildenafil's approval, it was evaluated in 18 phase II/III double-blind, placebo-controlled trials involving over 4,000 men. Success rates range from 74% (50mg dose) to 82% (100mg dose) compared to 27% with placebo. However, it has serious contraindications with nitrate medications and potential cardiovascular effects that require physician oversight.
Quick Summary
Government-manufactured pharmaceutical with standardized dosing and clear labeling. Active ingredient and amounts are precisely specified per regulatory requirements.
Sildenafil is the gold-standard, first-line pharmacological treatment for erectile dysfunction with over 25 years of clinical evidence. Success rates of 74-82% in clinical trials, with effectiveness maintained long-term.
Sildenafil has approximately 40% oral bioavailability with rapid absorption. Peak plasma concentration reached in 30-120 minutes.
Well-established safety profile over 25+ years, but carries serious contraindications with nitrates and requires medical supervision. Not suitable for self-medication.
Ingredient Breakdown
Sildenafil citrate is the sole active pharmaceutical ingredient. As a prescription medication, the dosing has been extensively studied in clinical trials across multiple populations. Available doses include 25mg, 50mg, and 100mg tablets.
Primary Ingredients
Sildenafil Citrate
PDE-5 Inhibitor / Erectile Dysfunction Treatment
Sildenafil inhibits phosphodiesterase type-5 (PDE-5), preventing the breakdown of cyclic GMP in the corpus cavernosum. This allows smooth muscle relaxation and increased blood flow to the penis during sexual stimulation. In clinical trials, 50mg was effective in 74% of men, while 100mg showed 82% effectiveness. The medication takes 30-60 minutes to work and effects last 3-4 hours. Systematic reviews and meta-analyses confirm it quadruples the success rate of intercourse compared to placebo. The 100mg dose showed greater IIEF-EF score improvement (10.7 vs 8.9, p=0.0287) and nearly doubled the odds of achieving completely rigid erections (OR=1.77) compared to 50mg.
Practical Recommendations
- Prescription Required: This is a prescription medication that requires physician evaluation and approval. Do not purchase from unregulated online sources or without medical consultation.
- Starting Dosage: Most patients start with 50mg taken 30-60 minutes before sexual activity. Your doctor may adjust to 25mg (if you have kidney/liver issues or are elderly) or increase to 100mg for better efficacy.
- CRITICAL: Nitrate Warning: NEVER combine sildenafil with nitrate medications (for chest pain/heart conditions) or recreational drugs containing nitrates ('poppers'). This combination can cause fatal blood pressure drops.
- Drug Interactions: Inform your doctor of ALL medications you're taking, including alpha-blockers, blood pressure medications, and other ED drugs. Avoid grapefruit juice while taking sildenafil.
- Emergency Symptoms: Seek immediate medical attention if you experience: erection lasting >4 hours, sudden vision loss, sudden hearing loss, or chest pain during sexual activity.
- Lifestyle Foundation: Sildenafil treats symptoms but not underlying causes. Maintain cardiovascular health through exercise, healthy diet, stress management, and avoiding smoking/excessive alcohol.
Is it Safe?
As a prescription pharmaceutical, sildenafil has a well-established safety profile from over 25 years of clinical use and post-market surveillance. However, it carries serious contraindications and warnings that require medical evaluation before use. The most critical concern is the absolute contraindication with nitrate medications, which can cause life-threatening hypotension.
Safety & Considerations
- CRITICAL: Nitrate Contraindication: NEVER take sildenafil if you use nitrate medications (nitroglycerin, isosorbide mononitrate, isosorbide dinitrate) or recreational drugs containing nitrates (poppers). This combination causes severe, potentially fatal hypotension. Single doses of sildenafil (100mg) decrease blood pressure by 8.3/5.3 mmHg in healthy individuals; with nitrates, the effect is synergistic and life-threatening.
- Cardiovascular Risks: Sexual activity carries cardiac risk. Consult your doctor if you have heart disease, recent heart attack or stroke (within 6 months), uncontrolled blood pressure, or left ventricular outflow obstruction. Not recommended with riociguat (Adempas) or other pulmonary hypertension medications.
- Priapism (Medical Emergency): Erections lasting >4 hours require immediate emergency care. Priapism can permanently damage penile tissue. Higher risk in patients with sickle cell anemia, multiple myeloma, leukemia, or anatomical penile deformation.
- Vision & Hearing Loss: Rare but serious: sudden vision loss (including permanent blindness) and sudden hearing loss have been reported. Stop medication immediately and seek emergency care if you experience sudden vision changes, blue tint to vision, or hearing loss. Sildenafil can cause temporary mild vision changes (blue tint, light sensitivity) in up to 11% of users.
- Common Side Effects (≥2%): Headache, flushing, dyspepsia (indigestion), nasal congestion, back pain, myalgia, nausea, dizziness, and rash. Most adverse events are transient and mild-to-moderate. The 100mg dose may cause more headaches and visual disturbances than 50mg.
- Drug Interactions: Multiple drug interactions exist. Inform your doctor of ALL medications including: alpha-blockers (may cause hypotension), CYP3A4 inhibitors (increase sildenafil levels), other ED medications. Do not take with grapefruit juice (increases drug levels).
- Not For Women Or Children: Sildenafil for erectile dysfunction is only indicated for adult men. Not approved for use by women (except pulmonary hypertension formulations under different trade names).
- Elderly & Liver/Kidney Disease: Dose adjustment may be needed for patients over 65 or with hepatic/renal impairment due to increased plasma levels and clearance issues. Start with 25mg in these populations.
The Science
Sildenafil is one of the most extensively studied medications for erectile dysfunction. Multiple randomized controlled trials, meta-analyses, and long-term studies have demonstrated robust efficacy across diverse patient populations. The medication has been evaluated in over 4,000 patients in controlled trials, with effectiveness maintained for at least 6 months of continuous use.
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