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How Long Does Sildenafil (Viagra) Stay in Your System? The Half-Life of Sildenafil Explained

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It is important to know the basics of any medication that you are taking, but for medications that you are taking “as needed” being in the know on how long your medication can last as well as the half-life is even more important.


“As needed” medications mean that you don’t just take them every day with your breakfast, you take them when you might need them. In the case of PDE-5 inhibitors like Sildenafil (brand name Viagra), you normally need to time out your dosage within a certain time frame before sexual activity. 


In the case of Sildenafil, if you take your dose too far spaced from when the romance starts, it may already be too cleared out of your system to have the optimal effect. If you take your Sildenafil too close to intimacy, it may not have adequate time to get into your system and start working.


With Sildenafil and other ED medications, timing can be everything.


Below, we will help you get a strong grasp of the details of the timing of Sildenafil including how long sildenafil stays in your system, how log sildenafil functions in your system, and some key tips on how to make your Sildenafil work the best for you.



How long does Sildenafil stay in your system?


The official half-life of sildenafil is 3-4 hours after an oral dose in the range of 25mg - 200mg. 


This means that after 3-4 hours, there will only be approximately ½ of the medication in your system as compared to the peak of the medication.


This doesn’t necessarily mean that it won’t still work for a bit after this time, it just means that half of it is already gone.


In the pharmacy world, we consider a medication to be more or less fully cleared from the system after 5 half-life cycles. So, in the case of sildenafil, this means that approximately 15 hours - 20 hours after you take your dose the medication will be almost fully gone. 


Below is a breakdown of the clearance of Sildenafil as calculated by the half life:


After 3-4 hours (1 half-life cycle): 50% of the peak Sildenafil remains

After 6-8 hours (2 half-life cycles): 25% of the peak Sildenafil remains

After 9-12 hours (3 half-life cycles): 12.5% of the peak Sildenafil remains

After 12-16 hours (4 half-life cycles): 6.25% of the peak Sildenafil remains

After 15 - 20 hours (5 half-life cycles): 3.125% of the peak Sildenafil remains


As you can see above, after about 5 half-life cycles, only a very small amount of the peak sildenafil level should still be in your body. 


But, it is important to note that there is still some Sildenafil remaining, which is why it is still important to avoid all medications that interact with or add onto Sildenafil for at least 24 hours after your last dose. This includes not taking more than 1 dose of any ED medication per day.



How long does Sildenafil function in your system?


As you can see above, the amount of time that some sildenafil is still in your body is around 1 full day. But, that is a separate question from how long Sildenafil may still be functioning in your body to help with your ED symptoms.


For most users of Sildenafil that are on a good dose for them (not too high, not too low), they will likely be able to experience adequate effects from Sildenafil to help with their ED symptoms up until the 1st half-life of the drug. This is about 3-4 hours after taking Sildenafil.


As we can see in the half-life chart above, there will definitely still be Sildenafil in your system after this amount of time, but it will likely not be enough to produce the same functionality as the first 3-4 hours.


If you find that this 3-4 hour window doesn’t quite suit you and your partner, you may be able to speak with your doctor about trying an ED medication with a longer half-life called Tadalafil (brand name Cialis).



Important note on the activity of Sildenafil


When discussing the activity window of Sildenafil, or any other ED medication, it is important to note that this time frame represents the window in which the drug may make it easier to achieve and keep an erection, not the amount of time the erection is supposed to last.


If you have an erection lasting 3-4 hours or longer, this is considered a medical emergency called priapism and you should seek medical care immediately. Priapism may cause damage to the penile tissues and needs to be treated by a professional.



Strut Health Sildenafil and Tadalafil prescriptions online


Here at Strut, we want to take the stigma away from getting medical care for potentially delicate situations, including sexual health concerns like ED.


We offer genuine Sildenafil and Tadalafil tablets online, discreetly. If your doctor deems one of these prescription ED medications suitable for your symptoms. If you are interested in seeing if an ED medication may be a good fit for you, you can have a free online questionnaire-based telemedicine consultation with our U.S. licensed doctors today.


If you are a good candidate for treatment, your prescription will be filled at a U.S. licensed pharmacy and shipped to your front door with our discreet and free shipping.


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