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Sexual Health/Sildenafil
Men's Sexual Health

SildenafilGeneric Viagra®

The clinically established treatment for erectile dysfunction — now prescribed online, reviewed by licensed providers, and shipped discreetly from U.S. pharmacies.

$2 per dose, starting at Placeholder pricing
100% online visit Licensed U.S. providers Discreet shipping No insurance needed
Meet sildenafil +
Sildenafil is the active ingredient in Viagra®, available as an affordable FDA-approved generic. It belongs to a class of medications called PDE5 inhibitors and is among the most widely studied treatments for erectile dysfunction.
How to take it +
Taken as needed, typically 30–60 minutes before sexual activity. Sexual stimulation is required for it to work. Your provider will recommend a starting dose based on your intake and health history.
Side effects to know +
Common, usually mild effects include headache, flushing, and nasal congestion. Sildenafil should never be combined with nitrates. Review all considerations with your provider before starting.
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[ DR PHOTO ]
Medically reviewed by Dr. A. Jimenez, MDBoard-certified, ForbiddenRx Medical Affairs · Last reviewed June 2026
Why sildenafil

A proven first step, made effortless

For most men exploring treatment for the first time, sildenafil is the clinically sensible place to start — affordable, well-understood, and flexible.

Decades of clinical use

One of the most prescribed and studied ED medications in the world, with a well-characterized profile.

Take only when you need it

As-needed dosing means no daily pill — ideal for spontaneity and trying treatment on your own terms.

Affordable generic

The same active ingredient as Viagra® at a fraction of the brand price through 503A partner pharmacies.

Dose flexibility

Available in 25 mg, 50 mg, and 100 mg so your provider can dial in what works for your body.

How it works

The science, in three steps

1

Blocks PDE5

Sildenafil inhibits the PDE5 enzyme, which normally breaks down the signal that allows an erection to form.

2

Blood flows in

With PDE5 paused, blood vessels relax and circulation to the penis increases when you're aroused.

3

Firm & ready

The result is a firmer erection that's easier to achieve and maintain — with natural arousal still required.

30–60
Minutes to onset
4–6
Hours of effect
3
Dose strengths
50
States served
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What is sildenafil?

Sildenafil citrate is the generic form of Viagra® — the original PDE5 inhibitor approved for erectile dysfunction. As a generic, it contains the identical active ingredient to the brand at a far more accessible price.

It's intended for use as needed before sexual activity rather than on a daily schedule. Because it relies on natural arousal to work, sildenafil supports your body's own response rather than overriding it.

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Dosing & safety

How to take it — safely

How to take sildenafil

  • OnsetTypically begins working within 30–60 minutes of taking your dose.
  • TimingTake roughly 1 hour before sexual activity for best results.
  • FrequencyUsed as-needed — not a daily medication. One dose per day maximum.
  • With foodA heavy or high-fat meal may delay how quickly it works.

Available strengths — your provider selects the right starting dose:

25 mg 50 mg 100 mg

Safety & side effects

⚠ Never combine with nitrates

Taking sildenafil with nitrate medications (often prescribed for chest pain or heart conditions) can cause a dangerous, life-threatening drop in blood pressure. Tell your provider about every medication you take.

  • Headache
  • Flushing
  • Nasal congestion
  • Indigestion or upset stomach
  • Temporary changes in vision (color tint, light sensitivity)

Seek immediate care for an erection lasting more than 4 hours (priapism) or sudden vision/hearing changes.

Compare your options

Which treatment fits you?

A side-by-side look at the ED options available through ForbiddenRx. Your provider helps you choose what's right.

Treatment What it is Onset Duration Form Price Rx required
Tadalafil Generic Cialis®, longer-acting PDE5 30–60 min Up to 36 hours Tablet $3/dose* Yes
3-in-1 Hard Mint Compounded blend, dissolvable 15–30 min Varies Troche / mint $4/dose* Yes
Branded Viagra Original brand-name sildenafil 30–60 min 4–6 hours Tablet $$$ /dose* Yes

*All pricing shown is placeholder for illustration only. Final pricing is confirmed during your visit.

Sildenafil
$2/dose*
Proven, affordable, as-needed.
Tadalafil
$3/dose*
Longer window of effect.
3-in-1 Mint
$4/dose*
Fast, dissolvable, discreet.
Branded Viagra
$$$*
The original brand-name.
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Keep the mood alive

Treatment shouldn't get in the way of the moment. Sildenafil's as-needed format is built around your life, not the other way around.

  • Discreet, unmarked packaging to your door
  • Automatic refills so you're never caught short
  • Message your provider anytime to adjust your plan
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Questions, answered

Sildenafil FAQ

Is sildenafil the same as Viagra? +
Sildenafil is the active ingredient in Viagra®, available as an FDA-approved generic. It contains the identical active compound as the brand-name product at a lower cost.
How quickly does it work? +
Most men find sildenafil begins working within 30–60 minutes. Taking it about an hour before activity, and avoiding heavy meals beforehand, can help. Natural sexual stimulation is still required.
Do I need a prescription? +
Yes. Sildenafil is a prescription medication. After your online visit, a licensed provider reviews your information. A prescription is not guaranteed and is subject to provider review of your health history.
Which dose is right for me? +
Sildenafil comes in 25 mg, 50 mg, and 100 mg. Your provider recommends a starting dose based on your intake form, and your plan can be adjusted over time based on how you respond.
What should I avoid while taking it? +
Never take sildenafil with nitrate medications — the combination can cause a dangerous drop in blood pressure. Limit alcohol, and disclose all medications and conditions to your provider.
Is my visit private? +
Yes. Your consultation is confidential, and medication ships in discreet, unmarked packaging. Your information is handled in accordance with applicable privacy standards.
Credibility you can verify

Care held to a higher standard

LegitScript Certified
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Licensed Providers
U.S. board-certified clinicians
503A Pharmacies
U.S.-based compounding partners
All 50 States
Nationwide telehealth coverage
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Related treatments

Ready when you are

Complete a quick online visit. A licensed provider reviews your information and, if appropriate, your sildenafil ships discreetly to your door.

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