Viagra's Mechanism for Blood Flow

Yet myth-based questions continue to follow the little blue pill around.

Can Viagra give you a never-ending erection? Let’s set the record straight with the help of urologist Drogo Montague, MD. Odds are you’ve seen a Viagra commercial and heard this warning: Seek immediate medical help for an erection lasting four or more hours.

• Viagra can improve confidence by helping men achieve and maintain an erection.
• Women do not take Viagra for sexual enhancement; research is ongoing.
• Viagra has been on the market since 1998 and is widely used worldwide.
• It may interact with other medications, including antifungals and antibiotics.
• Lifestyle changes, such as weight loss and quitting smoking, can improve ED.
• Viagra is classified as a phosphodiesterase type 5 inhibitor.
• Always store Viagra in a cool, dry place away from children.

It’s an attention-grabbing piece of cautionary advice. But the situation that it addresses — a condition known as priapism — is a relatively uncommon side effect of the medication, says Dr. Montague. A study published in 2020 categorized long-lasting erections from Viagra and other ED medications as a “rare event.” Researchers found 411 cases of drug-induced priapism while reviewing more than two decades worth of data. But your odds of problematic prolonged erections increase if you combine Viagra with certain penile injection therapies, notes Dr. Montague. “Combining the treatments has a cumulative effect — penile injection therapy makes your erections hard, and adding Viagra makes them harder and even more long-lasting,” he continues. “So stay on the safe side and don’t pair them.” Here’s a fun fact for you: Viagra was created to help your heart. Researchers initially developed Viagra to treat angina, a type of chest pain. Angina occurs when your heart doesn’t get enough oxygen-rich blood and starts working harder to compensate. Now, Viagra didn’t exactly shine as a treatment for angina … but the stiffer erections the little blue pill caused certainly stood out as a side benefit.

Further information

But a 2005 study of 16 patients with severe Raynaud's phenomenon that had not responded to other medications reported benefit from sildenafil in a dose of 50 mg twice a day. And a 2006 study of 40 Raynaud's patients reported similar benefits from vardenafil in a dose of 10 mg twice a day. Sildenafil was discovered by scientists looking for a new medication to dilate coronary arteries. It does that, but because it widens healthy coronary arteries more than diseased vessels, it has not been successful in treating angina. But it may have other benefits for cardiac patients.

Osphenia (Ospemifene)

In the first years of the Viagra era, research on sildenafil and the heart was devoted to making sure the drug was safe for the circulation. In most men with heart disease, it is. But several studies of patients with congestive heart failure also reported that the medication improves oxygen consumption, pulmonary artery pressure, and exercise capacity in these patients. Research shows that sildenafil helps the heart muscle relax properly, which could help patients with heart failure due to diastolic dysfunction. Another interesting property is sildenafil's ability to protect the heart from excessive stimulation by adrenaline. Which brings us back to the generic viagra professional sildenafil 100mg question regarding Viagra and your heart.

The erectile dysfunction medication isn’t harmful to your ticker when taken on its own. That’s an important caveat because Viagra should NOT be taken with heart medications that include nitrates. Like nitrates, Viagra helps dilate (or expand) blood vessels constricted by coronary artery disease.

Pregnancy & Lactation

Clinical trials will be needed to see which patients might benefit. It's the most speculative use for sildenafil, and it's far from clinical application. Still, it's an interesting area of new research. A European study of 25 men who had erectile dysfunction but no other circulatory disorders found that blood vessels in the brain responded to stress better after a 50-mg dose of sildenafil. More interesting results were reported by scientists in Michigan, who produced ischemic strokes in rats by temporarily blocking blood vessels.

Does Viagra work to treat ED?

During their recovery, the animals were divided into three groups. One received no treatment, another low-dose sildenafil, and the third high-dose sildenafil. The animals who got sildenafil recovered better, with the highest doses producing the best results. The scientists concluded that the medication actually stimulated the growth of new nerve cells in the brain tissue next to the stroke damage. It's far too early to know whether sildenafil may someday help people with strokes. Your blood pressure drops when this happens, as less force is needed to pump blood through your system. The worry if you take both Viagra and nitrates is that your blood pressure could drop too low, a condition known as hypotension. Abnormally low blood pressure increases your risk of a heart attack or stroke.

How should I take Viagra?

Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician. Don’t believe everything you’ve heard about ‘the little blue pill’ Image content: This image is available to view online. Physician's hand holding a blue pill in the palm of his hand, offering it to a patient. Those four words are all that’s required to identify viagra jelly sachets uk Viagra®, the brand name for a medication used to treat erectile dysfunction (ED).

Mild side effects

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. The medication, officially known as sildenafil, debuted in 1998. Today, it’s used by millions of men around the world when they want to … well, rise to the occasion during an amorous moment. Talk to your healthcare provider before taking Viagra with other medications. Taking Viagra to enhance your bedroom performance likely won’t make it more difficult for you to see your partner — unless you overdo it.

• Viagra may cause side effects like dizziness or upset stomach in some users.
• Alcohol consumption can reduce the effectiveness of Viagra.
• Avoid taking Viagra if you have heart problems without medical advice.
• The medication is available by prescription from a healthcare professional.
• Illegal or counterfeit Viagra can contain harmful ingredients.
• Tell your doctor about any health conditions before use.
• Viagra does not protect against sexually transmitted infections.

High doses of Viagra have been connected to temporary vision issues, reports the American Academy of Ophthalmology. But overall, the medication is considered low risk when it comes to eyesight.

• Viagra can help improve the quality of your sexual relationship.
• People should inform their doctor about any allergies before use.
• Viagra is part of a broader class of medications called PDE5 inhibitors.
• Sexual desire is still necessary for Viagra to be effective.
• Regular health check-ups can monitor the effects of the medication.
• Some users report improved self-esteem with proper use.
• Proper hydration can help reduce side effects like headaches.

There’s a slight chance, though, that the pill may color your world blue for a bit. Chemicals in Viagra can temporarily change how light hits your eyes, giving everything you see a short-lived blue tint. This reaction is more likely if you take a maximum dose of Viagra (100 milligrams). “This side effect can happen with higher doses, but it’s uncommon,” says Dr. Montague. Viagra increases blood flow to your penis, which can help you get and maintain an erection for whatever activity you have in mind. But responsibility for the “in mind” part of the process is on you. The little blue pill isn’t designed to increase libido or sex drive, clarifies Dr. Montague. Basically, think of Viagra as a performance enhancer as opposed to a mood setter. ED is more common with age, but that doesn’t mean it’s not an issue for the younger crowd. Studies show that nearly 40% of men are affected by ED by age 40. It can happen much, much earlier, too. Talking to your healthcare provider about ED and ED medications also may help you save your penis from injury. Having sex with an erection that’s barely “hard enough” can bend your penis and tear tissue that may scar while healing. As scar tissue isn’t elastic like healthy penile tissue, it can force your penis to bend with future erections. That can lead to a condition known as Peyronie’s disease. Taking Viagra or another ED medication can bring a firmness that prevents the issue. “If you’re having erectile dysfunction problems, you should feel confident going to your doctor no matter your age,” reassures Dr. Montague. “Many men are embarrassed, but they shouldn’t be.

4. Effects of Viagra on various organ systems in the Body

If you get your information about sildenafil from Super Bowl commercials or e-mail spam, you might dismiss it as a lifestyle drug of little real medical importance. In fact, it's a serious prescription medication that has helped millions of men who are distressed by an entirely legitimate medical problem. Because the drug acts on arteries beyond the penis, it can produce various side effects. That means it should only be prescribed by a personal physician who really knows you. And it also means that scientists are investigating uses for the drug in patients with an array of vascular disorders having nothing to do with sexual function.

Health News

They have nearly identical effects on ED as well as similar side effects. Because they are newer drugs, scientists are just beginning to study them for problems that don't involve sexuality. Sildenafil has already been licensed to treat men and women with pulmonary hypertension. Time will tell if any of these drugs will fill other potentials beyond promoting potency. As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Help is available, and it’s worth a try.” Viagra is approved for use to treat ED after age 18.

• Viagra’s patent expired, leading to generic versions being available.
• The medication should be taken at least half an hour before sex.
• Some men experience rapid or delayed onset of action.
• Sildenafil, the active compound, also treats pulmonary hypertension.
• It’s important to discuss potential drug interactions with your doctor.
• Viagra is not suitable for everyone, especially those with certain health issues.
• Side effects usually resolve within a few hours of taking the drug.

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