If you’re suffering from erectile dysfunction and looking to start treating your condition with a medication like Viagra, you probably have a lot of questions about how this class of drugs works, how long they last, and how long the medicine will stay in your system.
Since its release in 1998, Viagra, also known as the “little blue pill,” has become the gold standard for erectile dysfunction treatment.
Today, more than 25 million prescriptions have been written for Viagra.
Before you talk to your doctor about treating your erectile dysfunction, let’s talk about how Viagra works.
What is erectile dysfunction and what causes it?
Erectile dysfunction, or male impotence, is caused when blood flow to the penis is limiting the blood vessels, preventing a man from getting or keeping an erection hard enough for sex or any kind of sexual activity.
While there are many physical health conditions that can cause erectile dysfunction, the five most common causes are atherosclerosis (clogged arteries), high blood pressure, high cholesterol, diabetes, and obesity.
Lifestyle can play a role as well, with alcohol abuse, smoking, illegal drug use, side effects of other prescription medications (including those used to treat high blood pressure, heart disease, and depression), and side effects of over-the-counter medications such as antihistamines and Sudafed all having an impact on your body’s ability to get and keep an erection.
Depression, stress, and anxiety are psychological factors that can contribute to erectile dysfunction.
Erectile dysfunction is more than just embarrassing, frustrating, and inconvenient – it can also be the sign of a serious health issue.
If you notice a difference in your body’s erections and something seems abnormal, you should talk to your doctor about your symptoms for medical advice.
How does Viagra treat erectile dysfunction?
Viagra belongs to a class of drugs called PDE-5 inhibitors based on the chemical that they work on in the body.
In the first phase of an erection, a chemical called cGMP causes the tissues and muscles in the penis to relax, allowing blood to flow in.
Because the muscles are relaxed, the blood gets trapped, which causes an erection.
When cGMP starts breaking down, the erection ends as blood flows out of the penis.
Viagra works by blocking PDE-5, which is responsible for the breakdown of cGMP.
Since the cGMP does not break down, the tissues in the penis stay relaxed and engorged with blood, allowing you to keep an erection.
Because you need to be sexually aroused to have an erection, Viagra does not cause erections unless you’re in the mood.

How long does Viagra take to start working?
When it comes to the length of time that it takes to start working, Viagra, just like tadalafil, falls squarely in the middle of the spectrum between the slow-acting Cialis and Sildenafil and the fast-acting Levitra and Stendra.
On average, brand name Viagra takes approximately 30 to 60 minutes to take effect, but it may take up to two hours to reach full strength for some individuals.
The medication will take longer to work if you have eaten a high fat meal prior to taking it, and it may not be as effective.
If you’re especially concerned about making sure the medication works to its maximum effectiveness, don’t eat fatty foods such as steak, burgers, and lasagna for several hours before you take your pill.
Remember, you won’t get an erection without being sexually aroused through sexual stimulation, so take plenty of time to get into the mood before attempting sex.
For those with a long history of erectile dysfunction, performance anxiety can also come into play.
If this is the case for you, make sure you start slow and perhaps engage in some extra foreplay with your partner to give yourself time to become fully aroused.
How long does Viagra last?
As with so many things in life, the answer to the question “How long does Viagra last?” is “It depends.”
While Viagra is marketed to last four hours, for most people, effects will start to fade after two to three hours.
Some people may experience the effects of Viagra for five hours or more depending on the dosage.
Regardless of what dosage you take and how long Viagra lasts in your body, the medication will not impact your time to orgasm.
To date, no studies have shown that Viagra influences the amount of time it takes to reach orgasm. Some men may be able to have multiple erections from one dose of Viagra depending on timing and dosage strength.
Each man undergoes what is called a refractory period following orgasm; this is the period of time it takes for the body to recover after orgasm before having another erection.
For some men, the refractory period may only last a couple hours, while others may take days to recover.
What factors determine how long Viagra lasts?
There are many factors that can influence how long Viagra lasts in your body.
Some of these factors are within your control, while others are not. Factors influencing the length of time Viagra lasts include:
- Dosage: Lower dosages of Viagra are metabolized and eliminated more quickly, so the 25 mg and 50 mg doses of the medication will leave your body more quickly than the 100 mg dose. While increasing your dosage may be an option, a higher dose is not suitable for everyone. Do not increase your dosage without talking to your doctor first.
- Age: This is one situation where being older pays off! Our metabolism slows as we age, so Viagra will stay in your system longer the older that you are. Viagra works noticeably longer for men over the age of 65 for this reason.
- Diet: You’ve already heard that eating high-fat foods can cause Viagra to take effect more slowly. That’s true, but it’s also true that fatty foods will slow the metabolism of your medication, meaning that it will stay in your system longer.
- Alcohol intake: It’s not just what you eat that matters – drinking alcohol can also impact how long Viagra lasts in your body! Alcohol decreases blood flow to the penis, which makes Viagra less effective and shortens the length of time that it lasts. Skip the alcohol if you’re planning on taking your medication that evening, or limit your drinks.
- Medications: While medications like nitrates can cause serious and potentially life-threatening side effects when combined with Viagra, there are other medications that interact with the medication and increase its elimination time. If you are taking antibiotics like erythromycin, clarithromycin, and ciprofloxacin, you may notice that Viagra is eliminated from your system more quickly.
- Overall health: Some health conditions, including diabetes, multiple sclerosis, and heart conditions like atherosclerosis, are known to reduce the effectiveness of Viagra and increase the rate at which the medication is eliminated from the body. On the other hand, those with kidney issues can extend the life cycle of the drug by slowing the rate at which it is metabolized.
- Psychological state: Like it or not, your psychological state has a lot to do with Viagra’s effectiveness and the length of time it lasts. Anxiety, depression, and stress can all negatively impact your body’s response to Viagra.
What can I do to help Viagra last longer?
Viagra is effective for up to 85 percent of erectile dysfunction patients at a strength of 100 mg, but there are steps you can take to make sure it works as well and as long as possible.
Reduce your risk: As previously mentioned, some of the conditions that cause erectile dysfunction are preventable and reversible.
Help reduce your erectile dysfunction risk factors by watching your weight, increasing your exercise, eating healthy meals, quitting smoking, and reducing stress.
- Skip the fatty foods: Viagra is less effective and takes longer to work when taken with or immediately following a high fat or heavy meal. Wait at least two hours after a fatty meal to take your medication.
- Choose wisely: In order to find the medication that works best for you, you may have to try several options. All medications are formulated differently, so make sure you give your doctor your complete list of medical conditions and medical history while trying to choose a drug.
- Speak up: Your doctor needs to know if you take nitrates, which are often prescribed for chest pain, or guanylate cyclase stimulators such as Adempas (riociuguat), which are prescribed for pulmonary hypertension, as these medications can cause serious side effects when taken with Viagra.
- Wait a minute (or 30): Don’t panic if your Viagra doesn’t work right away. It generally takes 30-60 minutes to kick in, but can take up to two hours.
- Consider upping your dose: Viagra’s effectiveness increases the higher your dosage is, with 85 percent of men taking 100 mg successfully treated for erectile dysfunction. If your current dose isn’t working the way you had hoped, talk to your doctor about increasing your dose.
- Be patient: Some patients see a greater response to Viagra after several doses. Don’t panic if your medication doesn’t give you the results you expected the first time you try it.
- Don’t panic: Anxiety and depression about your sexual performance can play a huge role in your erectile dysfunction. Give your medication time to work and yourself plenty of time to get in the mood.
How long does Viagra stay in my system?
Viagra is a relatively fast-acting medication that wears off quickly.
A typical dose of 25 mg or 50 mg will stay in your body for roughly two to three hours, but it may take up to six hours for some people to fully process the drug.
Higher dosages of the medication will take longer to fully leave the system; a 100 mg dose of Viagra may take up to eight hours to leave the body. The length of time that Viagra stays in your system will be influenced by the factors previously mentioned.
References, Studies and Sources:
https://en.wikipedia.org/wiki/Erectile_dysfunction
https://www.drugs.com/viagra.html
Owner, entrepreneur, and health enthusiast.
Chris is one of the Co-Founders of Pharmacists.org. An entrepreneur at heart, Chris has been building and writing in consumer health for over 10 years. In addition to Pharmacists.org, Chris and his Acme Health LLC Brand Team own and operate Diabetic.org and the USA Rx Pharmacy Discount Card powered by Pharmacists.org.
Chris has a CFA (Chartered Financial Analyst) designation and is a proud member of the American Medical Writer’s Association (AMWA), the International Society for Medical Publication Professionals (ISMPP), the National Association of Science Writers (NASW), the Council of Science Editors, the Author’s Guild, and the Editorial Freelance Association (EFA).
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