Viagra Sildenafil Genuine Enhances Endurance Men's Health

 Introduction to US Viagra:

Viagra is a medication for treating ED developed by Pfizer, USA. In 1998, Pfizer's Sildenafil Citrate (Viagra) was successfully launched and gained widespread customer trust and purchases. According to statistics, four "Viagra" pills are consumed every second worldwide, fully validating its efficacy. It is one of the most effective drugs for improving erectile dysfunction!


Mechanism of Action of Viagra:

The sildenafil component is rapidly absorbed after oral administration, with an absolute bioavailability of about 40%. Its pharmacokinetic parameters are dose-proportional within the recommended dose range. Elimination is primarily hepatic (via cytochrome P450 isoenzyme 3A4 pathway), producing an active metabolite similar in nature to sildenafil. Potent inhibitors of cytochrome P450 3A4 (CYP450 3A4) such as erythromycin, ketoconazole, itraconazole, and non-specific inhibitors of cytochrome P450 (CYP450) such as cimetidine, when used with sildenafil, may lead to increased plasma levels of sildenafil. The elimination half-life of sildenafil and its metabolites is about 4 hours. When taken on an empty stomach at doses of 25-100 mg, maximum plasma concentration is reached within about 1 hour (optimal effect when taken one hour before activity)


Dosage and Side Effects of Viagra:

For most patients, the recommended dose is 50 mg (half a pill), taken about 1 hour before sexual activity; however, it can be taken anytime from 0.5 to 4 hours before activity. Based on efficacy and tolerability, the dose may be increased to 100 mg (the maximum recommended dose) or decreased to 25 mg (quarter pill), taken at most once daily. [Adverse Reactions] Mild dizziness, flushing, indigestion, nasal congestion, visual abnormalities, etc. Visual abnormalities are mild and transient, mainly manifested as color tinge, increased light sensitivity, or blurred vision (these mild adverse reactions quickly disappear as the drug is diluted and cause no harm to the body)


Precautions for Using Viagra:

1. The interaction between sildenafil and nitrate drugs affecting blood pressure can last from the start of administration throughout the entire 6-hour observation period. Therefore, under any circumstances, simultaneous use of sildenafil with organic nitrates or NO-donating drugs (such as sodium nitroprusside) is contraindicated.

2. If food is consumed, especially fatty foods, taking Viagra requires 1 hour to be absorbed and take effect.

3. After taking the medication, sexual stimulation such as caressing or hugging is required to achieve an erection, and if stimulation stops, the erection will subside. The effect can last up to 4 hours, and without sexual stimulation, there will be no sustained erection. Viagra does not enhance libido or sexual function.