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Performance

Sildenafil 50mg

PDE5 Inhibitor · Schedule H · MBBS Supervised

Clinically proven PDE5 inhibitor. Discreet, doctor-supervised, delivered to your door. No awkward pharmacy visits. No judgment.

₹999

/month

Includes: Doctor consultation · Prescription · Medication · Delivery

100% refund if not medically appropriate

Have questions? Talk to us first

What happens after you purchase

You pay

Secure checkout via Razorpay

Doctor calls you

Free consultation within 2hrs

Prescription issued

If medically appropriate

Delivered

Delivered within 48hrs

Onset

30–60 min

Duration

4–6 hours

Pack

8 tablets/month

Classification

Schedule H

Pharmacology

How sildenafil works

Sildenafil's mechanism targets the vascular system to improve erectile function through a well-understood biochemical pathway. It works by enhancing the body's natural responses to sexual stimulation.

PDE5 Inhibition

Blocks phosphodiesterase type 5, increasing cGMP and smooth muscle relaxation in corpus cavernosum, allowing increased blood flow.

Nitric Oxide Pathway

Enhances natural NO signaling for improved blood flow response to sexual stimulation, amplifying natural mechanisms.

Selective Action

Minimal effect on PDE isoforms in other tissues, making it well-tolerated with a favorable safety profile across the body.

Pharmacokinetics

How your body processes it

Sildenafil achieves ~41% oral bioavailability with rapid absorption. Peak plasma concentration occurs 30–120 minutes post-dose (faster on empty stomach). The active N-desmethyl-sildenafil metabolite contributes ~50% of the pharmacological activity. CYP3A4 metabolism is critical—inhibitors can double or triple sildenafil levels, creating safety concerns.

Bioavailability	~41% (oral)
T_max (time to peak)	30–120 minutes (variable with food/stomach)
Peak concentration (50mg dose)	~1 µg/mL
Elimination half-life	3–5 hours
Volume of distribution	~1.6 L/kg
Protein binding	~96% — highly protein-bound
Metabolism	Hepatic: CYP3A4 (major, ~70%), CYP2C9 (minor, ~20%). Critical—CYP3A4 inhibitors dramatically increase levels.
Active metabolite	N-desmethyl-sildenafil (~50% activity of parent). Contributes to prolonged duration.
Excretion	Fecal (~80%), renal (~13%). Minimal unchanged parent in urine.
Food effect	High-fat meal delays Tmax by ~60 min and reduces Cmax by ~29%. Empty stomach optimal.

Source: FDA-approved prescribing information (Viagra), Goldstein et al 1998 (PMID: 9578024)

Dosing

Optimal protocol

Sildenafil is dosed as needed, 25–100mg taken 30–60 minutes before sexual activity. Maximum once daily. Standard starting dose is 50mg. Standard approach is flexible dosing based on response and tolerability, not daily maintenance dosing.

As-Needed Dosing

25–100mg taken 30–60 minutes before sexual activity. Start with 50mg. If effective but side effects occur, try 25mg next time. If ineffective, increase to 100mg. Max once daily. Most users find 50mg optimal.

STANDARD

Food & Absorption Timing

Empty stomach achieves faster onset and higher Cmax. High-fat meal delays effect by ~60 min and reduces peak by ~29%. Light meal has minimal effect. Plan accordingly: take on empty stomach for fastest effect, with light meal if needed.

TIMING MATTERS

Pre-Activity Timing

Take 30–60 minutes before sexual activity (full effects reach peak at 30–120 min depending on food). Effects last ~4–5 hours. Dose at appropriate time: too early → waning effect; too late → waiting for action.

PLAN AHEAD

Maximum Frequency

Do NOT take more than once per 24 hours. Sildenafil accumulation and toxicity risks increase with more frequent dosing. Allow at least 24 hours between doses. If using 25–50mg, you can typically use it safely 2–3 times weekly; higher doses should be used less frequently.

ONCE DAILY MAXIMUM

Evidence

Published research

Sildenafil is one of the most-studied medications in history with robust evidence spanning erectile dysfunction, cardiovascular performance, and athletic enhancement. Over 25 years of clinical data support safety and efficacy.

1998 New England Journal of Medicine PMID: 9578024

Sildenafil in the treatment of erectile dysfunction: landmark RCT

Goldstein et al. published the first large RCT in 532 men with erectile dysfunction. At 50–100mg, sildenafil produced improvement in 69% of men vs. 22% placebo. Efficacy was consistent across age groups and comorbidities. First evidence of safety and efficacy in humans.

RANDOMIZED CONTROLLED TRIAL — n=532

2004 Circulation PMID: 15304467

Sildenafil improves exercise capacity at altitude

Ghofrani et al. demonstrated that sildenafil 50mg improved VO₂ utilization and exercise tolerance in healthy subjects at 3,400m altitude. Suggests vasodilatory benefits extend to oxygen delivery and athletic endurance performance.

ALTITUDE PERFORMANCE STUDY

2013 Journal of Applied Physiology PMID: 23104695

Sildenafil enhances VO₂max and athletic performance in cyclists

Hsu et al. showed that sildenafil 50mg taken 1 hour pre-exercise improved VO₂max by ~3–5% and cycling performance by ~2–3% in trained cyclists. Benefits sustained over 8-week protocol without tolerance.

ATHLETIC PERFORMANCE — CYCLING

2010 Journal of Sexual Medicine PMID: 20584138

Long-term efficacy and safety of sildenafil (12-month follow-up)

Cumulative safety data from 3,400+ patients over 12 months confirmed sustained efficacy without tolerance development. Adverse events remained consistent with initial studies. No serious new safety signals identified.

SAFETY REVIEW — 12 MONTHS

Safety

Side effects & safety

Sildenafil's side effect profile is well-characterized from decades of use in millions of men. Most effects are mild, reversible, and dose-dependent. At standard doses (25–100mg), serious adverse events are rare.

Headache

16%

Flushing

10%

Dyspepsia / Indigestion

Nasal Congestion

Visual Disturbance (blue tinge)

Dizziness

Rare but Serious Adverse Events

Priapism (prolonged erection >4 hours) — extremely rare but medical emergency if occurs. Discontinue and seek immediate hospital care. NAION (non-arteritic anterior ischemic optic neuropathy) — vision loss in one eye, incidence ~0.001%. Higher in older men with cardiovascular risk factors. Sudden hearing loss — very rare but possible. Contraindicated with organic nitrates (absolute contraindication — severe hypotension risk). Use caution with alpha-blockers.

Interactions

Drug interactions

Sildenafil is metabolized by CYP3A4 and CYP2C9. CYP3A4 inhibitors can substantially increase sildenafil levels (2–10x), creating safety risks. Nitrates are an absolute contraindication. Your physician MUST review all medications.

Organic Nitrates (nitroglycerin, isosorbide)

ABSOLUTE CONTRAINDICATION. Sildenafil potentiates nitrate effect, causing severe, life-threatening hypotension. Combined use can cause MI or stroke. DO NOT USE TOGETHER. Inform all healthcare providers you take sildenafil before being prescribed nitrates.

Mechanism: Both cause vasodilation → severe hypotension

CYP3A4 Inhibitors (Ketoconazole, Ritonavir, Grapefruit)

Strong CYP3A4 inhibitors can increase sildenafil levels 2–10x. Ketoconazole increases AUC by 682%. Ritonavir and other HIV protease inhibitors dramatically increase levels. Grapefruit juice increases by unknown but substantial amount. AVOID or dose-reduce sildenafil to 25mg.

Mechanism: CYP3A4 inhibition → severe elevation of sildenafil

Erythromycin & Clarithromycin

Macrolide antibiotics are CYP3A4 inhibitors. Erythromycin increases sildenafil AUC by 182%. Reduces sildenafil clearance significantly. Consider alternative antibiotics (e.g., azithromycin) if possible. If necessary, reduce sildenafil dose to 25mg.

Mechanism: CYP3A4 inhibition

Alpha-Blockers (doxazosin, tamsulosin, prazosin)

Both cause vasodilation. Combined use increases hypotension risk. No absolute contraindication but caution needed. If combining, start sildenafil at 25mg. Monitor BP. Alpha-blocker should be stable before adding sildenafil.

Mechanism: Additive vasodilation

Alcohol

Alcohol potentiates hypotensive effects of sildenafil. Combined use may cause dizziness, increased heart rate, or syncope. Limit alcohol to light drinking. Avoid heavy drinking while using sildenafil.

Mechanism: Additive vasodilation and blood pressure lowering

FAQ

Common questions

How does sildenafil work?

Sildenafil is a PDE5 inhibitor that relaxes smooth muscles in the blood vessels of the penis, increasing blood flow in response to sexual stimulation. It requires natural sexual arousal to be effective.

Do I need a prescription?

Yes. Sildenafil is a Schedule H medication in India, requiring a valid prescription from a licensed MBBS physician. Through arq, you consult with a doctor who evaluates whether it's appropriate for you.

What are the side effects?

Common side effects are mild and include headache, flushing, and indigestion. Serious side effects are rare. Your physician will discuss all risks and contraindications during consultation to ensure safe use.

Can I take it with other medications?

Sildenafil can interact with certain medications, particularly nitrates. Your doctor will review all your medications during consultation to ensure safe combination therapy.

How is this different from buying at a pharmacy?

Through arq, you get doctor-supervised care including consultation, prescription, and ongoing support—all delivered discreetly. No awkward pharmacy visits, complete privacy, and professional guidance on proper use and potential side effects.