How long does sildenafil last for?

You have just popped your blue pill out of its blister pack, anticipating a night of romance. You quickly check the remaining tablets, but there is only one left. You wonder how long the first tablet will last and if you have enough for the next two days. You wish you had brought more tablets and read a blog like this before you left for your weekend away so that you would know how long sildenafil lasts.

In this article, we will cover all things relating to timing, such as how long it takes for the sildenafil to reach your system and how long it lasts. However, before we get stuck into the pharmacokinetics (don’t worry, we will explain this term later) – we will go over some of the basics of both erectile dysfunction and sildenafil, which is the generic version of that famous blue pill, Viagra.

If you already know enough about a topic, you can use the handy navigational table below to skip to the relevant areas.

What is erectile dysfunction?

Erectile dysfunction (ED) occurs when a man struggles to get or maintain an erection firm enough for satisfying sexual activity (Muneer et al., 2014). Unlike erections, the number of men experiencing erectile dysfunction (ED) is rising worldwide, impacting many aspects of their health and well-being. This trend is likely to keep growing, with predictions estimating that around 322 million men globally could face ED in the future (Ayta et al., 1999).

The one-off experience of failing to get an erection is usually not a cause for concern; I mean, everyone can have an “off day”. However, when the erectile dysfunction starts to persist for over six months, then it is described as chronic erectile dysfunction.

Chronic health issues like heart disease, high cholesterol, high blood pressure (Orimoloye et al., 2019) and depression are strongly linked to increased rates of erectile dysfunction (ED). Diabetes is another long-term condition that is a significant factor in the development of erectile dysfunction (Maiorino et al., 2014). In diabetes, ED happens for a few reasons. Constant high blood sugar can damage blood vessels (a condition called endothelial dysfunction), create harmful byproducts, increase cellular stress, and damage nerves—leading to a reduced ability to get and maintain an erection (Guay et al., 2007).

Nerve damage caused by diabetes leads to erectile dysfunction

Diabetes can cause two types of nerve damage: peripheral and autonomic. Peripheral nerve damage can disrupt the signals between the brain and the penis, making it harder to feel aroused. It also weakens the muscles that help control blood flow in the penis (Fowler et al., 1988).

Clogged arteries limit blood flow to the penis.

Cardiovascular issues, like high blood pressure and clogged arteries, can limit blood flow to the penis, which is essential for erections (Schwartz et al., 2011). These conditions make it harder for blood vessels to widen, which can directly impact the ability to get an erection.

So, you can kind of think of the development of chronic erectile dysfunction as a kind of canary in the mineshaft or an early warning system telling you about the health of your blood vessels. Researchers now believe there is a window of about three years from the onset of erectile dysfunction to the development of more serious cardiovascular complications (Montorsi et al., 2003).

Low testosterone and erectile dysfunction

If you haven’t been living under a rock, then you should know how low testosterone levels can impact a man’s health. In the past, men put the symptoms of low testosterone, or hypogonadism, down to ageing, but now we know that it’s all down to testosterone levels.

Erectile dysfunction is one of the first signs that your testosterone levels may be low, especially the loss of “morning wood” or the early morning erection (Schardein et al., 2022). So, if you are starting to experience erectile dysfunction more often, then it may be a good idea to get your testosterone levels checked.

FREE TRT consultation

If you want further advice on testosterone replacement therapy or TRT, please contact us for a FREE TRT consultation.

Medical Mojo offers private consultations to discuss safe and effective treatments, including lifestyle changes, medications, or hormone therapy options. For more information, please contact us or visit medicalmojo.co.uk.

What is sildenafil?

Sildenafil is the generic version of that popular blue pill, Viagra. It is available in three strengths:

• Sildenafil 25mg
• Sildenafil 50mg
• Sildenafil 100mg

It is recommended to start with the sildenafil 50mg and then adjust the dose to sildenafil 25mg or sildenafil 100mg depending on the side effects and whether an erection is possible with the sildenafil 50mg tablet.

Sildenafil belongs to a class of drugs known as phosphodiesterase type 5 inhibitors, which also include the following:

• Cialis (Tadalafil)
• Spedra (Avanafil)
• Levitra (Vardenafil)

These medications help by relaxing the blood vessels in the penis, which increases blood flow to help create an erection when you are sexually aroused.

How does sildenafil work?

Viagra, or sildenafil, is a medication that helps men with erectile dysfunction (ED) by boosting blood flow to the penis, making it easier to get and maintain an erection. It belongs to a type of drug called PDE5 inhibitors, which work by raising levels of a chemical in the body called cGMP (Corbin et al.,2004). Think of cGMP as a signal that opens up the “floodgates” for blood flow to the penis. When cGMP levels go up, more blood flows in, increasing pressure and creating an erection.

Sildenafil supports this process by blocking an enzyme called PDE5, which usually lowers cGMP levels. By blocking PDE5, sildenafil keeps cGMP levels high, allowing blood to flow more easily. However, it still requires sexual arousal to work, as it only enhances the natural process (Andersson et al., 2018).

What is pharmacokinetics?

Remember that scientific term in the introduction? Well, this is the time for a quick definition. The pharmacokinetic properties of a drug comprise all the different steps from its entry into the body to its elimination from the body.

Pharmacokinetics is a term that comes from Greek, where “pharmakon” means “drug” and ” kinetikos” means “movement” (Bereda G., 2022). It’s basically the study of what happens to a drug in your body once you take it—how the body absorbs it, how it moves around in your bloodstream, how it gets broken down, and how it eventually leaves your system.

Pharmacokinetics covers four main steps, often remembered by the acronym ADME (Bereda G., 2022):

1. Absorption – how the drug enters the blood.
2. Distribution – how it spreads throughout the body.
3. Metabolism – how it’s broken down, often in the liver.
4. Excretion – how the drug and its byproducts are removed from the body, like through urine.

So, pharmacokinetics is all about how the body “handles” a drug, tracking its journey from entry to exit.

When to take sildenafil?

When discussing erection dysfunction and treatments like sildenafil and Viagra, timing matters, and that requires that you know the following:

• How long does it take sildenafil to work?
• How long does sildenafil last for?

This will allow you to time the taking of sildenafil so that it works to bring on an erection at the right moment, and the effects have worn off by the time you have that important board meeting.

Sildenafil is an example of a faster-acting PDE5 inhibitor and is a “one-and-done” medication, meaning that you only need to take it when required, and it doesn’t require daily dosing.

When you take a single dose of sildenafil by mouth, it’s absorbed quickly, reaching its peak in the bloodstream within about an hour. The concentration of sildenafil in your blood generally matches the dose you took. Eating a meal might slow the absorption slightly, but it doesn’t change how much of the drug your body absorbs. Since the liver processes part of the drug right after it’s absorbed, only about 41% reaches the bloodstream, a measure known as its bioavailability (Nichols et al., 2002).

How long does sildenafil remain in the body?

Sildenafil is cleared from your system fairly quickly, with half of it breaking down in about 3–4 hours across doses ranging from 25 mg to 100 mg. The time taken for this to happen is called the half-life.

Sildenafil’s main metabolite, which remains in the system with a similar breakdown time, is about half as potent. The effects of sildenafil can last up to three times its half-life, and some men report noticeable effects up to 24 hours later (McCullough, A.R. 2002).

This quick action makes it perfect for on-demand use in treating erectile dysfunction, and studies confirm it’s well-tolerated within its typical dosage range (25–100 mg) (Hatzimouratidis K., 2006).

How long does sildenafil last?

Sildenafil typically works at full strength for about 4-6 hours (Eardley et al., 2002).  After this period, its effects gradually fade, though some mild benefits may linger as long as they remain in your bloodstream. The exact duration can vary depending on factors like your overall health, age, dosage, and level of sexual activity.

Remember, sildenafil (and other erectile dysfunction medications) won’t keep you continuously erect for the entire time it’s in your system. It simply makes it easier to get an erection when you’re sexually stimulated. After ejaculation, your erection will naturally subside as it usually would.

Sildenafil drug interactions

Sildenafil is broken down in the liver by enzymes called cytochrome p-450. Some drugs, like cimetidine, erythromycin, and ketoconazole, can slow down this process, which might lead to sildenafil staying in the system longer. Sometimes, this could mean you might have to adjust the dose. However, during clinical trials, men who took these enzyme-inhibiting drugs with sildenafil didn’t show higher side effects than others, even without adjusting the dose.

Sildenafil is generally safe, but if taken with the protease inhibitor ritonavir (an antiviral medication primarily used to treat and manage HIV/AIDS), which also uses the same metabolic pathways, it’s advised not to exceed 25 mg of sildenafil within 48 hours.

How soon does sildenafil start to work?

So, after you have taken your sildenafil tablet, how soon does it start working its magic to cause an erection? The good thing about sildenafil is that it is one of the faster-acting PDE5 inhibitors, which means it is absorbed quickly, reaching its peak in the bloodstream within about an hour. So, after taking sildenafil, you can expect an erection within 60 minutes.

Studies have found that the onset of action was achieved within a median time of 27 minutes after sildenafil dosing. There have been reports of achieving erections as quickly as within 12 minutes, but the majority of patients (71%) achieved an erection within 30 minutes (Eardley et al., 2002). These findings are in line with studies that have found the time to peak plasma concentration of sildenafil after oral dosing (30–120 min).

Why does it take so long to get an erection after taking sildenafil?

Even though there has been a recorded incidence of a man achieving an erection after 12 minutes of taking Viagra (Eardley et al., 2002), overall, studies have found that an erection is achieved anywhere between half an hour to 3 hours (Boolell et al., 1996). The reason for this lag is that the tablet has to take the arduous journey through an acidic lake (the stomach), squeeze through walls (small intestine) and evade the body’s border guards (the liver) before it reaches the circulation where it is transported to the penis.

It can take up to an hour for the effects to appear, and not all of the drug reaches circulation; only about 41% of the original dose makes it (Nichols et al., 2002). This is why oral tablets have much higher doses; we know not all active ingredients are absorbed.

Do you want a faster-acting sildenafil?

If you would like a faster onset of action, why not try the compounded triple combination erectile dysfunction soluble oral patches? These are designed to be absorbed from the buccal mucosa or the inside of the mouth, which has a rich blood supply. When drugs are absorbed via this route, they don’t have to make the long journey, passing through the stomach, small intestine and liver to reach the circulation.

The Medical Mojo compounded triple combination erectile dysfunction soluble oral patch

The soluble compounded oral patch uses the buccal mucosa to provide a VIP pass straight into the bloodstream. This means that if you take a compounded triple combination erectile dysfunction soluble oral patch, it will get to work within 15 minutes to half an hour.

The other benefit of the compounded soluble oral patch is that we have combined the fast and short-acting sildenafil with the longer-acting tadalafil, which means you get an erection sooner, and the effects last for up to 36 hours. As if that is not enough, we have also added l-arginine to increase the vasodilatory effects, which means you get a stronger erection. More blood flow equals a stronger erection.

The triple combination erectile dysfunction compounded soluble oral patch is available in the following strengths:

Strength	High	Medium	Low
Contains	Sildenafil 35mg Tadalafil 10mg L-arginine 2.5mg	Sildenafil 20mg Tadalafil 15mg L-arginine 2.5mg	Sildenafil 10mg Tadalafil 20mg L-arginine 2.5mg
Product

The benefits of buccal administration of sildenafil

There are several advantages of the buccal route (Chinna et al., 2011), including:

• the ease of administration,
• faster absorbance rate of the drug,
• bypasses first-pass metabolism in the liver. Remember that only 41% of sildenafil in an oral tablet makes it into circulation after passing through the liver,
• avoids low GI absorbance and
• rapid acting

Can I take sildenafil with food?

Sildenafil or Viagra is best taken on an empty stomach to allow for faster absorption. Food can delay absorption and the time it takes to reach peak concentrations in the blood. A high-fat meal can delay absorption, and the time to peak concentrations can be extended to over an hour, with an average reduction in peak concentrations of 29% (Nichols et al., 2002).

Can I take sildenafil with alcohol?

Alcohol is the social lubricant that facilitates the use of sildenafil in the first place. However, does taking alcohol affect the absorption of alcohol? The absorption of sildenafil is affected by anything that delays gastric emptying, such as a high-fat meal. As far as the effects of alcohol on the absorption of sildenafil are concerned, the effects are negligible (Hatzimouratidis K., 2006). However, that is not to say that this is a green light to combine sildenafil with alcohol, which we strongly advise against. To find out why, read our blog on “Can I drink alcohol while taking sildenafil?”

How the different dosages of sildenafil compare

The effectiveness and duration of sildenafil also depend on the dose. Higher doses, like 100mg, are prescribed as the maximum to ensure both effectiveness and safety, as higher amounts can increase side effects, especially related to the heart. Lower doses, such as 25mg, may only last for about 2-3 hours, depending on individual factors like weight and severity of erectile dysfunction. A starting dose of 50mg is typical for most men, which can then be adjusted up or down depending on the response and side effects (Hatzimouratidis K., 2006).

Understanding these variations can help you get the best results from your treatment.

Sildenafil vs. other erectile dysfunction medications

Studies have been carried out on the pharmacokinetics of the three following PDE5 inhibitors used in erectile dysfunction:

• Sildenafil
• Vardenafil
• Tadalafil

The table below summarises the results (Porst et al., 2004).

Vardenafil works faster than sildenafil

So, from the study above, we can observe that the PDE5 inhibitor that produced an erection the fastest was vardenafil. It caused an erection to occur in 40 minutes, while sildenafil took up to an hour, and tadalafil took two hours to cause an erection.

Tadalafil lasts longer than sildenafil

Which PDE5 inhibitor lasts the longest? In the table above, the half-life, which is the time it takes for the drug’s concentration to be reduced by 50%, was measured. Sildenafil had the shortest half-life, with 3.7 hours, while tadalafil had the longest, with 17.5 hours.

Which is the most potent PDE5 inhibitor?

In in-vitro studies, vardenafil showed the highest biochemical potency, which is between 9 and 25-fold higher than that of sildenafil and between 13 and 48-fold higher as compared to tadalafil (Porst et al., 2004).

Which erectile dysfunction tablets last longer?

When it comes to oral treatments for erectile dysfunction, there are two main types based on how long they last:

• Short-acting (4-6 hours): This category includes Sildenafil (Viagra), Vardenafil (Levitra), (Porst et al., 2004).and Avanafil (Spedra) (Evans et al., 2015). These meds kick in quickly, making them great for planned occasions when you only need a short window of effect.
• Long-acting (up to 36 hours): Tadalafil (Cialis) is the primary option in this group, often called the “weekend pill” because it can support erections for up to 36 hours (Evans et al., 2015) which can be convenient for more spontaneous situations.

If you’re looking for something that will provide performance support for a longer period, like a weekend away, Tadalafil might be the way to go. However, if you’re after one-time reliability, sildenafil is still a top choice.

Quick summary on how long does sildenafil last for

• Sildenafil works best within about an hour and is faster on an empty stomach.
• It offers 2-6 hours of effectiveness but won’t keep you erect the whole time—only when aroused.
• Effects taper off and are gone by the next day.
• Taking more than recommended won’t help and can cause side effects.
• Ideal for occasional support.

If you want to try sildenafil, complete an online consultation at Medical Mojo to get started.

Want to know more about sildenafil and other erectile dysfunction treatments?

If you are curious to know more about sildenafil or Viagra, we have written several informative blog articles, including the following:

• Understanding Viagra headaches: causes and solutions
• Why does Viagra cause heartburn?
• Can Viagra cause blood clots?
• Can Viagra cause a stroke?
• Does Viagra make you last longer?
• Can I drink alcohol while taking sildenafil?
• Can Viagra make you bigger?

Getting guidance for erectile dysfunction

You should not feel shy talking about erectile dysfunction; as we mentioned previously, think of it as the canary in the mineshaft, warning you that something is wrong with your blood vessels. It may even be that your blood vessels are fine, and could be a psychological problem.

 Whatever the cause, the team at Medical Mojo are here to help. We can guide you on the correct treatment, advise you on what to do when the PDE5 inhibitors don’t work, and even help you design a completely personalised solution. However, the first step is reaching out to us. So, if you have any questions, please don’t hesitate to contact us.

Why choose Medical Mojo for sexual health support?

If you’re considering sildenafil or looking for other ways to tackle erectile dysfunction, it’s important that the treatment selected is appropriate for you. Our healthcare questionnaires will ensure that the treatment is safe for you, but if you want to learn more or need some further guidance, please do not hesitate to contact us.

Medical Mojo offers private, supportive telehealth services for men facing sensitive issues like erectile dysfunction. Their team of knowledgeable pharmacists, doctors, and therapists provide guidance on sildenafil and other options, helping you make informed, confident choices.

So, why choose Medical Mojo for support for your sexual health?

• Private, non-judgemental consultations from the comfort of your home
• Personalised recommendations based on your complete health profile
• Health screenings to confirm if sildenafil is the right treatment for you
• Ongoing support and follow-up while using sildenafil
• Clear guidance on what to realistically expect from sildenafil
• Holistic advice on lifestyle changes to support sexual health
• An ethos on basing all treatments and support on the latest evidence-based medicine

With Medicalmojo.co.uk, you’ll gain a realistic understanding of what sildenafil can and cannot do to help with erectile dysfunction and your overall sexual health. This helps you to set healthy expectations and make well-informed treatment decisions. For more information, contact info@medicalmojo.co.uk.

Disclaimer: This article is for informational purposes only and does not replace professional medical advice.

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