Viagra dosage for erectile dysfunction (ED) is usually 50 to 100 milligrams (mg), but those over 65 may start at 25 mg. Your doctor will also need to consider possible drug interactions.

If you’re new to Viagra, here’s the lowdown on how much you need hen you’re getting started.

It depends on a few factors, including your age and why you’re taking it, since Viagra is not only used to treat ED.

Your doctor will tell you how much you should take.

How much Viagra should I take the first time?

For help with erections, the recommended dose for adults ages 18 to 64 years old is 50 milligrams (mg). Adults over age 65 often start with the lower dose, 25 mg.

The dose could be increased to 100 mg depending on how effective it is and how well it’s tolerated.

How to take Viagra safely

Certain medications and conditions may interact with Viagra, so it’s important to tell your doctor about any medications you take before you are prescribed Viagra. Some medications and conditions that interact with Viagra include:

  • Ritonavir: Viagra should be taken at 25 mg per 48 hours in order to be used safely along with this drug, since ritonavir increases the concentration of Viagra.
  • CYP3A4 inhibitors: Viagra should be taken at 25-mg doses with CYP3A4 inhibitors. CYP3A4 inhibitors also increase the concentration of Viagra.
  • Alpha-blockers: You should be stabilized on alpha-blocker therapy prior to using Viagra in order to use it safely, and it should be prescribed at the lowest dose. Otherwise, the two medications together could cause low blood pressure.
  • Cardiovascular conditions: If you have cardiovascular issues, it may be best to steer clear of Viagra completely, since Viagra can make you more likely to go into cardiac arrest.

In any case, it’s important to also beware of side effects like lightheadedness, change in vision, and nausea when taking Viagra, and speak with your doctor if you experience any of these. For severe side effects like prolonged erections and loss of vision or hearing, stop taking the drug and immediately seek medical attention.

Take Viagra just once a day if it’s being used for ED.

Taking more than a single prescribed dose in the same day increases your chance of prolonged erection, called priapism, and other serious side effects.

No. Stick to your prescribed dose to avoid any unpleasant and potentially serious effects.

You can try masturbating or other methods of sexual stimulation to see whether this helps. If it still does not work, speak with your doctor about adjusting your dose.

There are other ED treatments available if needed, including lifestyle changes that may help.

Ideally, take Viagra an hour before sexual activity. But it can be taken 30 minutes to 4 hours before sexual activity, too.

How you take Viagra matters when it comes to effectiveness.

Eat a light meal beforehand

Viagra can be taken with or without food, but if you like to fuel up before sexual activity, try to keep your meal choice light.

Eating a large or high fat meal before you take it can delay absorption, meaning it’ll take longer to take effect.

If you’re anting it to work right away, eat a lighter meal.

Already ate a large meal? You might want to wait a couple of hours to allow enough time for digestion before taking it.

Give yourself time for it to work

Do not take the pill and expect to get an erection right away. Plan on giving yourself some time for it to work.

You can take it up to 4 hours before having sex, so no need to rush or stress about it.

Don’t drink alcohol after taking Viagra

If you like a glass of wine or another alcoholic beverage to unwind before sex, you should be fine.

But drinking more than that after taking Viagra could decrease its effectiveness.

Moderate to heavy drinking can make it more difficult to get an erection. Also, Viagra can lower blood pressure. Combining it with alcohol can increase this effect.

If your blood pressure drops, symptoms like dizziness, lightheadedness, and headache could also decrease effectiveness.

Get in the mood

Viagra will not work if you are not sexually aroused.

If you’re going to take it before then, you’ll need to help it along by getting in the mood.

Need a little help? Enjoy something that you find sexually stimulating, such as:

Viagra normally starts to work within 30 to 60 minutes but can take as long as 2 hours.

If you’re relaxed and sexually aroused, it could take effect sooner.

It depends on individual factors. Your age, overall health, and what’s in your stomach when you take it can all affect how long it lasts.

Typically, Viagra can last up to 4 hours, but many users say it begins to wear off within 2 or 3 hours. Some have reported it lasting up to 5 hours.

In case you’re wondering, you will not have an erection the entire time. It just means you’ll be able to get it during that window.

Usually, your erection will go away after you ejaculate.

Like Viagra, most ED drugs can be taken 30 to 60 minutes before sex.

The exception is avanfil (Stendra), which is the fastest-acting ED medication available. It only takes 15 to 30 minutes to kick in, depending on the dose.

When it comes to duration, tadalafil (Cialis) is the longest lasting and works for up to 36 hours.

Viagra works by increasing blood flow to the penis so you can get hard enough, long enough to engage in sexual activity.

Everyone is different, but it’s definitely possible.

Your stamina, natural refractory period, and level of arousal can determine how many times you’ll be able to ejaculate before the medication wears off.

Yes, as is the case with all medications.

Below are the most common side effects of Viagra. Speak with your doctor if you experience any of these symptoms for an extended period of time:

  • headache
  • feeling sick
  • back and muscle pain
  • dizziness
  • rash
  • flushing
  • stuffy or runny nose
  • vision problems, such as blurred vision or a blue hue

Though not common, some serious side effects have been reported.

Medical emergency

Stop taking Viagra and call 911 or your local emergency services, or go to the nearest emergency room, if you experience any of these symptoms:

  • an erection that does not go away (priapism), which can cause permanent damage
  • sudden vision loss in one or both eyes, which may be a sign of a serious condition called nonarteritic anterior ischemic optic neuropathy
  • sudden changes in hearing, including tinnitus, decrease in hearing, or hearing loss
  • chest pain or other signs of a heart problem or stroke, such as shortness of breath, confusion, trouble speaking, or nausea and vomiting
  • signs of a severe allergic reaction, which may include fever, trouble swallowing, skin blisters, or swelling of the face, eyes, or tongue
  • seizures

There’s no hard and fast rule here. It really comes down to you and your doctor.

Viagra is not effective for everyone.

In some cases, your doctor may recommend trying it over the course of a few weeks or months.

If you’ve tried it a few times and feel you’ve done your part to make it as effective as possible, let your doctor know.

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Resist the urge to take Viagra recreationally. Be sure it’s prescribed by a doctor who’s aware of your medical history.

Recreational Viagra is a thing, and so is counterfeit Viagra. Both are risky and can lead to much more serious side effects.

A doctor will prescribe the safest and most effective dose based on your health and needs.

When taken as prescribed, Viagra can help you get an erection so you can engage in sexual activity, but don’t expect it to do all the work.

Take it as directed and make sure to help it along by being aroused when you use it.

If you’re not happy with your results, speak with your doctor about other available treatments.