Medically reviewed by Notre équipe éditoriale
Written by Anne-Sophie Laignel
Last updated 1/22/2025 - 5 min read
Viagra 25 mg works by inhibiting the enzyme PDE5 (phosphodiesterase type 5), which is responsible for breaking down cyclic guanosine monophosphate (cGMP) in the penis. cGMP plays a crucial role in the erection process. During sexual arousal, nitric oxide is released, stimulating the production of cGMP in the cells of the penis. This process causes the relaxation of smooth muscles in the arteries of the penis, allowing blood to flow more freely into the area, thereby leading to an erection.
However, the enzyme PDE5 reduces the amount of cGMP in the penis, which decreases the body's ability to maintain an erection. By inhibiting PDE5, Viagra helps to maintain higher levels of cGMP in the penis, thereby improving blood flow and facilitating the achievement and maintenance of an erection when the man is sexually stimulated.
It is important to note that Viagra does not automatically induce an erection. The medication only works when sexual arousal is present, and it does not produce erections without stimulation.
Viagra 25 mg is generally prescribed to men who have mild to moderate erectile dysfunction or who are at risk of side effects due to increased sensitivity to medication. This dosage allows for the assessment of the drug's effectiveness while minimizing the risk of adverse effects.
Viagra 25 mg should be taken about 30 to 60 minutes before sexual intercourse. It starts to work quickly, and its maximum effect is reached after about 1 to 2 hours. The medication can be taken with or without food, but it is important to note that the absorption of Viagra can be delayed if it is taken after a meal high in fat.
Viagra 25 mg should not be taken more than once a day. If the effect of the medication is not sufficient, the doctor may adjust the dose, increasing the amount to 50 mg or 100 mg, depending on the patient's needs and their response to the treatment.
The duration of the effect of Viagra 25 mg is usually about 4 to 6 hours. This means that a man can achieve and maintain an erection during this period, under the effect of sexual stimulation. However, it is important to note that the erection will not be continuous throughout this period, but it can occur at several times during this 4 to 6-hour window.
The effects of Viagra usually begin to wear off after about 4 hours. If an erection is not achieved within this time frame or if it fades before sexual activity is completed, it may be necessary to take another dose, but this should always be done following medical advice to avoid any risk of side effects.
It is also important to note that the duration of Viagra's effect can vary from one person to another. Some may experience a longer effect, while others may find that it wears off more quickly. Individual factors, such as age, health status, other medications, and food, can influence this duration.
Like any medication, Viagra 25 mg can cause side effects. The most common adverse effects are mild and temporary. They include:
In rare cases, more serious side effects may occur. This can include:
It is imperative to consult a doctor if any of these serious side effects occur or if mild side effects persist or become bothersome.
Viagra 25 mg should not be used by certain individuals, especially those who:
Before starting a Viagra treatment, it is crucial to consult a doctor to discuss medical history and any other medications you might be taking.
Viagra 25 mg is an effective option for treating erectile dysfunction, especially in men who have a moderate response to higher doses. It works by inhibiting PDE5 and improving blood flow to the penis, thus facilitating an erection in response to sexual stimulation. With a duration of action of 4 to 6 hours, it provides a sufficient period for the completion of sexual activity. However, as with any medication, it is important to follow your doctor's recommendations to minimize the risk of side effects and ensure the effectiveness of the treatment.
The IIEF-5 Index is a recognized tool to assess erectile function. Answer 5 questions and discover your score and options in complete confidentiality.
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