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Viagra® (sildenafil citrate)

Viagra® is a medication that’s used to treat erectile dysfunction (ED). It works by expanding the blood vessels that go to the penis to deliver better blood flow, improving your ability to get and maintain an erection.

Sildenafil citrate is the generic version of Viagra. The two medications are identical in chemistry and effectiveness. Sildenafil is a cheaper, more widely available option.

Dosage of Viagra depends on the severity of your ED. Start a free assessment today to receive a personalized care plan to treat your ED.

It is common for patients who use Viagra® to treat ED take their medication as an oral tablet between 30 minutes and one hour before sexual activity as needed. However, it’s important to talk to your doctor about the best sildenafil dosage and routine for you.

Viagra works best when taken on an empty stomach, and patients must combine it with sexual stimulation to induce an erection. The effects of sildenafil last for about five hours on average, but your erection should not. If your erection lasts more than four hours, call your doctor.

To treat PAH, your doctor will prescribe the correct dosage of sildenafil based on your condition and other medicines you are taking. Most patients with PAH take sildenafil in liquid form, either through an oral syringe or an IV injection, up to three times a day. Your doctor will show you how to correctly mix and administer the medication to get the correct amount every time.

For some patients, Viagra® can cause mild to moderate side effects, even when taken as directed. Common adverse reactions include:

  • Muscle pain or back pain
  • Flushing, rash, or warm skin on the face, neck, or chest
  • Indigestion, nausea, or diarrhea
  • Headache or tenderness around the eyes
  • Bloody, congested, or runny nose
  • Difficulty sleeping (insomnia)

Occasionally, Viagra can cause more serious side effects, including:

  • Blurred vision
  • Light sensitivity
  • Decreased color vision or difficulties visually differentiating between colors
  • Buzzing or ringing in the ears
  • Memory problems
  • Confusion
  • Lightheadedness
  • Unusual weakness or exhaustion
  • Difficulty breathing

If you take sildenafil and then experience any of the following:

  • Feeling faint
  • Difficulty breathing
  • Sudden changes in vision, vision loss, or hearing loss
  • Swollen hands, ankles, or feet
  • Chest pain or heart attack symptoms
  • A seizure
  • A painful erection or an erection that lasts more than four hours

you may need immediate medical attention. Call your doctor or go to your nearest emergency room.

Viagra® is only FDA-approved for erectile dysfunction in men; it is not approved for sexual dysfunction in women. Both male and female patients can take sildenafil to treat pulmonary arterial hypertension.

Viagra can cause health complications in people with certain pre-existing conditions and interact poorly with certain medications. So tell your doctor about any current health conditions, prescription medications you take, and over-the-counter medicines, herbal supplements, or street drugs you may use.

You should not take Viagra with any other drugs or devices meant to encourage erections. Also remember that sildenafil does not protect against HIV/AIDS or sexually transmitted diseases. Always use any precautions to stay safe when engaging in sexual activities.

Viagra makes certain drugs less effective, leading to health complications. Nearly 300 medications and street drugs are known to interact with sildenafil, but some combine more poorly than others.

Medications that interact extremely poorly with Viagra include but are not limited to:

  • Alpha-blockers
  • Amprenavir
  • Amyl nitrate (“poppers”)
  • Atazanavir
  • Boceprevir
  • Ceritinib
  • Clarithromycin
  • Cobicistat
  • Darunavir
  • Delavirdine
  • Erythromycin
  • Fosamprenavir
  • Idelalisib
  • Indinavir
  • Isosorbide
  • Isosorbide dinitrate
  • Isosorbide mononitrate
  • Itraconazole
  • Ketoconazole
  • Lonafarnib
  • Nefazodone
  • Nelfinavir
  • Nitric Oxide
  • Nitroglycerin
  • Nitroprusside
  • Riociguat
  • Ritonavir
  • Saquinavir
  • Telaprevir
  • Telithromycin
  • Troleandomycin
  • Tucatinib
  • Voriconazole

If you take any drugs listed above or any other medication that you worry may interact poorly with Viagra, talk to your doctor before you stop taking any current medications or start taking new ones.

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Calculate the price of your generic Viagra® prescription.

Sildenafil

25 mg

11

per month

Save 50%+ compared to other pharmacies

Tablet

Quantity: 6

Get Sildenafil from K Health for a fraction of the cost.

Others

5 mg

$1.80

$2.50+

10 mg

$2.70

$5.00+

20 mg

$4.50

$10.00+

25 mg

$4.90

$12.50+

50 mg

$5.10

$15.00+

100 mg

$5.40

$20.00+

Price reflects a 10% discount when ordering a 3-month supply.

Personalized ED treatment made simple (and discreet).

1

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Answer a few questions about your habits and history to see if treatment from K is right for you.

2

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Let us know your preferred medication, dosage, quantity and delivery schedule.

3

Review
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Your personalized treatment plan and prescription info will be shared within 24 hours.

4

Get your
medication

Get your medication

Your prescription will arrive within two days after approving your treatment plan.

Have any questions?

How much Viagra should I take the first time?

Only take the dose of Viagra that your doctor prescribes to you; any more, and you risk developing serious side effects. No matter what your dosage is, only take one tablet per 24-hour period.

How long does it take for Viagra to work?

You should take Viagra about an hour before sexual activity. Remember that it’s ideally taken on an empty stomach because having a high-fat meal beforehand can slow its effects.

How does Viagra work?

Viagra is a phosphodiesterase-5 inhibitor (PDE5 inhibitor) that blocks a specific enzyme from breaking down the molecule cyclic guanosine monophosphate (cGMP). cGMP helps the arteries in your penis widen so that more blood vessels can flow into it during periods of sexual stimulation. By blocking the enzyme that breaks it down, Viagra improves blood flow and helps men more easily achieve an erection.

How long does Viagra last?

Viagra is taken an hour before sexual activity, and the effects typically 4-5 hours. However, your erection should not last that long. If you have an erection for more than four hours, call your doctor.

Can you buy Viagra or Cialis online?

You can buy Viagra® and Cialis® online if you have a prescription from a doctor. With K Health, you can text with a doctor, get a generic Viagra® or Cialis® prescription, and get your medication shipped directly to your home.

Can you buy tadalafil online?

You can buy tadalafil online if you have a prescription from a doctor. With K Health, you can text with a doctor, get a tadalafil prescription, and get your medication shipped directly to your home.

Can you buy sildenafil online?

You can buy sildenafil online if you have a prescription from a doctor. With K Health, you can text with a doctor, get a sildenafil prescription, and get your medication shipped directly to your home.

Can you buy erectile dysfunction medication online?

Yes, you can buy erectile dysfunction medication online, but you will need a prescription from a doctor to facilitate the purchase. With K Health, you can text with a doctor and get your ED prescription delivered straight to your door.