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Generic Viagra (sildenafil) is an alternative to the branded Viagra drug that can be used for treating erectile dysfunction (ED). It’s now sold by many manufacturers, including online pharmacies like Roman, Hims, and Lemonaid.
- Best generic Viagra service with clear and transparent pricing: Roman Sildenafil | Skip to review
- Best for generic Viagra and other sexual health-related products: Hims Sildenafil | Skip to review
- Best for generic Viagra and other health and wellness medications: Lemonaid Sildenafil | Skip to review
- Best price for generic Viagra when bought in bulk: Optum Store Sildenafil | Skip to review
If you are experiencing the symptoms of erectile dysfunction (ED), you may have considered using Viagra or a similar ED medication as a possible treatment.
But if you’ve searched for places to buy Viagra online, you will have no doubt noticed its price tag, too. Since Viagra is a brand-name medication, the price of Viagra is very high and may not currently work within your budget.
Thankfully, a generic version of the popular medication — sildenafil — is now widely available from a number of different drug manufacturers at a fraction of the cost. But with so many different providers out there, it can be a challenge researching which companies or online services you can trust.
To help clear things up, we took a closer look at many of the top services that can prescribe and ship sildenafil directly to your home so that you can have the facts you need to get your ED treatment started.
While some of what’s sold as generic Viagra online is fake, several reputable companies sell sildenafil online. Each of the companies below has been vetted by our team for medical and business standards. Learn more here.
Sildenafil citrate (sildenafil), often referred to as “generic Viagra,” is the same active ingredient used in Viagra. Viagra also contains small amounts of inactive ingredients. These ingredients give the pill its form and make it easier for your body to metabolize them.
One of the primary causes of ED is a buildup of the phosphodiesterase type 5 (PDE5) enzyme that restricts blood flow to the penis and prevents or lessens the firmness of an erection. Sildenafil works as a PDE5 inhibitor, which blocks the effect of PDE5 and allows more unrestricted blood flow — making an erection more likely.
How do PDE5 inhibitors work?
Sildenafil doesn’t cure ED. It treats ED symptoms. Likewise, sildenafil doesn’t cure pulmonary hypertension (PH) — elevated blood pressure in the arteries of the lungs and in the right side of the heart. It just helps control blood pressure in the arteries in the lungs.
Sildenafil is in a class of medications called PDE5 inhibitors. These drugs restrict the action of phosphodiesterase enzymes, which break down cyclic guanosine monophosphate. This is a type of molecule that relaxes smooth muscle tissue in the body, such as those in the blood vessels that allow the penis to become erect. Taking sildenafil improves circulation by helping the arteries relax enough to fill more easily with blood.
Sildenafil is quickly absorbed into the bloodstream, reaching a maximum concentration in about 1 hour for most users. Generic Viagra, like other PDE5 inhibitors, can cause a drop in blood pressure. If you take medications for blood pressure control or tend to have low blood pressure, ask your doctor if it’s safe to use sildenafil.
Sildenafil doesn’t trigger an erection on its own, nor does it increase sexual desire. Sexual stimulation is still required. However, for most healthy people, sildenafil can make an erection easier to get.
A
Instead of the “little blue pill,” as Viagra is known, sildenafil is often sold as a little white pill by Viagra’s competitors. The pill’s appearance does not change its effectiveness or how it works in the body.
While generic sildenafil and Viagra are equally safe and effective, the medications have one key difference: price. Viagra costs around $60–$70 per tablet. Generic sildenafil can range from $2–$18 per pill, depending on the manufacturer and dose.
The pharmaceutical giant Pfizer discovered the ED benefits of sildenafil by accident.
Researchers were testing the medication to treat high blood pressure and angina — chest pain associated with heart disease. They found that the medication was especially effective at inducing erections. The Food and Drug Administration (FDA) approved Viagra in 1998, making it the first oral drug specifically prescribed for ED.
Pfizer was also the first to introduce generic Viagra through a subsidiary called Greenstone. Other companies around the world also manufacture sildenafil pills, including:
- Teva Pharmaceuticals
- Aurobindo
- Cambia
- Mylan
- Bristol Labs
Avoiding fake Viagra
Viagra and other ED medications are some of the most counterfeited drugs. It’s important to speak with a doctor to seek treatment and get medications through a pharmacy.
Sildenafil is available at most retail pharmacy locations and several reputable online retailers, so there’s no need to buy sildenafil from companies not regulated by the FDA.
Sildenafil is best known as a treatment for ED, the inability to get or keep an erection. Sildenafil is meant to be taken before having sex, with the understanding that its effects last only a few hours.
Sildenafil is also approved for treating PH. Revatio is the brand name of sildenafil prescribed for PH. It’s worth noting that while Revatio and Viagra have the same active ingredient, Revatio is FDA-indicated for treating PH specifically and you shouldn’t take Revatio instead of Viagra or alongside Viagra to treat ED.
In the United States, sildenafil for ED or PH requires a prescription. The United Kingdom allows for over-the-counter (OTC) sales of the drug, in part to discourage the market for fake sildenafil. Sildenafil is one of the most counterfeited drugs in the world.
Generic Viagra (sildenafil) is available as a 20-, 25-, 50-, and 100-milligram (mg) pill and in liquid form. It’s meant to be taken as needed — about an hour before sex — but shouldn’t be taken more than once per day. The 50-mg dose is standard, though your doctor may start you on a 25-mg dose to see if that’s enough.
Sildenafil may cause side effects, most of which are minor and temporary. Some of the most common are:
- headaches
- flushing, or a feeling of warmth under the skin
- heartburn
- diarrhea
- insomnia
- tingling in the limbs
- muscle aches
- sensitivity to light
Serious side effects of sildenafil
More serious side effects should prompt an immediate call to your doctor or 911. They include:
- erection that is painful or lasts longer than 4 hours (priapism)
- blurry vision or sudden and severe loss of vision
- diminished hearing
- ringing in ears
- dizziness or lightheadedness
- fainting
- shortness of breath
- chest pain
- itching or burning during urination
- rash
How long does it take for generic Viagra to take effect?
For ED, take sildenafil as needed, ideally 1 hour before intercourse. However, sildenafil may be effective as soon as 30 minutes before intercourse and may still be effective 3 or 4 hours later.
After 4 hours, the effects of sildenafil tend to wear off. It’s recommended that you take sildenafil no more than once daily.
Like any medication, sildenafil can have potentially serious interactions with other drugs, alcohol, and even some foods.
Blood pressure and heart medications
One of the most serious interactions can come from combining PDE5 inhibitors with nitrates or compounds containing nitrates. Several studies, including a
This is why you should discuss any medications that you’re taking with your doctor before starting any new medication. This can reduce the chances of a dangerous interaction.
If you take other medications for high blood pressure, you may be at risk of experiencing a dangerous drop in blood pressure. These include:
A drop in blood pressure can result in:
- dizziness
- headache
- fainting or falling
Severe blood pressure drops can also result in less oxygen moving through your organs.
Other ED medications
Avoid taking sildenafil with any other ED medications. The combination can lower blood pressure, causing fainting, dizziness, and in some rare cases, heart attack.
Alcohol
Alcohol and sildenafil can combine to lower blood pressure too much. Avoid alcohol if you’re taking sildenafil.
Grapefruit
The only real food interaction with generic Viagra is grapefruit and grapefruit juice. These products can raise the levels of sildenafil in your body but can also delay the time the drug takes effect.
Cytochrome P450
Similar to grapefruit, medications known as cytochrome P450 (CP450) inhibitors and substrates can delay how long it takes sildenafil to work and can increase your chance of side effects. CP450 inducers, such as modafinil, reduce the effects of sildenafil if taken at the same time.
CP450 medications include:
- cimetidine
- clopidogrel
- chloramphenicol
- fluvoxamine
- omeprazole
- modafinil
| Name | Price for sildenafil* | Dosage available for sildenafil* | ED medications available |
| Roman | $4–$10 per dose | 25–100 mg | branded Viagra, sildenafil, branded Cialis, generic Cialis, generic daily Cialis |
| Hims | $4–$10 per dose | 25–100 mg | branded Viagra, sildenafil, branded Cialis, generic Cialis |
| Lemonaid | $2 per dose | 20 mg | sildenafil, tadalafil |
| Optum Store | $1–$6 per dose | 20–100 mg | branded Viagra, generic Viagra |
*Prices accurate as of November 2023
There are a number of different treatments for ED. In addition to medications or other medical interventions, maintaining a healthy lifestyle can affect the success of your ED treatment.
Sildenafil is just one of several ED medications on the market.
Other oral medications
The four major PDE5 inhibitors are:
- sildenafil (Viagra)
- tadalafil (Cialis)
- vardenafil (Levitra)
- avanafil (Stendra)
All those medications, except avanafil (Stendra), are available as generic medications.
Penis pump
There are some nonpharmacological treatments for ED, including a vacuum erection device, also known as an ED pump.
It works by placing a seal around the end of the penis and attracting blood to the arteries in the penis by air suction.
Surgery and injections
Penile implants and penile injections to treat ED are other options to consider. Talk with a urologist to learn more about treatments you may want to try.
While you may be familiar with Viagra and its effectiveness, you might be understandably cautious about a generic version of Viagra.
So, if you have questions about how well generic Viagra works or where to buy it from a reputable source, it’s a good idea to meet with a doctor or healthcare professional.
If you are experiencing symptoms of ED and are considering a generic version of Viagra, your doctor can prescribe a generic alternative to ensure it is safe and FDA-approved.
It’s important to avoid any generic alternative not prescribed by a doctor or fulfilled by a reputable pharmacy. Prescriptions not filled through legitimate channels may not be FDA-approved, may have inaccurate labeling on the packaging, and may have ineffective or potentially harmful ingredients.
Sildenafil, or generic Viagra, is the non-branded version of the popular ED drug. It’s virtually identical to the brand-name drug, except it may be a different color (instead of blue, like Viagra) and costs a lot less.
Generic Viagra usually costs anywhere from $2–$10 for each tablet, depending on the dose, manufacturer, and pharmacy.
This is the general price you can find through subscription services like Roman, Hims, Lemonaid, and Optum Store.
You may also encounter a wider price range when filling a prescription at your local pharmacy. Your price can vary even more if you use a discount card from the pharmacy or a third party, or if your insurance provider covers or doesn’t cover generic Viagra.
Before purchasing your medication, it’s always worthwhile to inquire about the price from several different pharmacies or companies to help you find the best price for your budget.
No. In most countries, including the United States, Viagra is not available without a prescription.
However, in 2017, Viagra became available over the counter in the United Kingdom to combat the counterfeit market and improve access.
In the United States and most other countries, generic Viagra is only available with a prescription.
However, many new telehealth services make it easier to get a prescription without making an in-person appointment with a doctor.
There are also a few OTC alternatives to Viagra that may be worth exploring as well.
If a doctor prescribes 100 mg of sildenafil, or Viagra, it’s safe to use — provided you have shared your medical history and other medications you’re currently taking with your doctor.
This is on the high end of available doses and may only be necessary for people with more severe ED symptoms.
In most cases, if you’re new to taking ED medications, your doctor will likely start you on a lower dose, which would be increased if you don’t get your desired results at a lower dose.
A frequent misunderstanding with ED medications is the higher the dose, the better your results will be.
But the truth is, a higher dose won’t make your erections any harder or help you maintain an erection any longer after the point of orgasm if a lower dose can effectively address your ED symptoms.
Additionally, a person not experiencing ED symptoms who takes ED medication will likely not experience any changes, even if they take a high dose.
In fact, if the medication is taken without a prescription or not taken as prescribed, you could experience very serious side effects if it negatively interacts with other medications you may be taking.
Generic Viagra, or sildenafil citrate, works the same as Viagra, but at a lower cost.
While Pfizer still manufactures the “little blue pill,” other companies, globally and in the U.S., make sildenafil. It may look different, but it’s still an effective treatment for ED.