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Viagra
Last reviewed: 04.07.2025
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Viagra helps restore a healthy response to sexual arousal. The physiological process that leads to an erection occurs when nitric oxide is secreted within the cavernous body as a result of sexual stimulation.
NO stimulates the activity of a special enzyme called guanylate cyclase. This leads to an increase in the cGMP element. There is also a relaxation of the corpus cavernosum muscles and potentiation of blood circulation inside the penis.
Indications Viagra
It is used in the case of development of various erectile disorders (usually they are organic, psychogenic or mixed in nature).
Pharmacodynamics
Sildenafil is the active component of the drug; it is a selective inhibitor of the PDE-5 component, which ensures the processes of the cGMP element decay inside the cavernous body. The drug has a peripheral effect on penile erection. It should be taken into account that sildenafil does not have a direct relaxing effect on the cavernous body, but affects the relaxing activity of nitric oxide. For the drug to begin to act, the man must feel sexual arousal.
The medication is tolerated without complications; volunteers did not experience significant clinical deviations after a single dose of no more than 0.1 g.
Dosing and administration
The medication is taken orally, approximately 60 minutes before the expected start of sexual intercourse. The required dose per day is 50 mg of the substance (1 time). Taking into account personal tolerance and the effectiveness of the medication, the dosage can be reduced to 25 mg or increased to 0.1 g. A maximum of 0.1 g of the substance is allowed per day.
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Use Viagra during pregnancy
Viagra is used only in men.
Contraindications
Main contraindications:
- severe intolerance to the components of the drug;
- the presence of anatomical deformities of the penis (for example, cavernous fibrosis, Peyronie's disease or angulation);
- strong tendency to bleeding;
- ulcers in the gastrointestinal tract in the active phase;
- problems with liver function (especially liver failure or cirrhosis);
- diseases that lead to the development of priapism (including myeloma, leukemia, or sickle cell anemia);
- increased or decreased blood pressure (severe intensity);
- various heart diseases (a dangerous type of arrhythmia, unstable angina or heart failure).
In the next six months after a myocardial infarction or stroke, it is prohibited to use Viagra. Also, the drug cannot be prescribed in combination with nitric oxide donors and nitrates. In addition, the drug is not used in men who are prohibited from sexual activity.
Side effects Viagra
The medicine is often tolerated without complications. Only occasionally do the following side effects appear:
- CNS disorders: dizziness, insomnia, or increased muscle tone;
- disorders of cardiovascular function: headaches, hot flashes or vasodilation;
- musculoskeletal disorders: pain affecting muscles and joints;
- problems with the gastrointestinal tract: diarrhea, dyspepsia or nausea;
- epidermal disorders: rashes;
- symptoms related to the senses: visual acuity disorder, distortion of color perception, increased light perception and conjunctivitis;
- Respiratory tract infections: pharyngitis, infections in the respiratory tract, sinusitis, breathing disorders, nasal congestion and runny nose;
- disorders of urogenital function: problems with prostate function and infections of the urethra;
- other disorders: pain in the abdomen or back and flu-like symptoms. Priapism is occasionally observed.
Overdose
Tests have shown that Viagra intoxication causes an increase in the severity of side effects.
In such cases, symptomatic measures are required. Dialysis will be ineffective because the active element of the drug is synthesized with blood plasma protein at high speed and very actively.
Interactions with other drugs
Cimetidine, erythromycin, and ketoconazole decrease drug clearance rates with a further increase in plasma levels of sildenafil.
The combination of Viagra with Na nitroprusside leads to the potentiation of its antiplatelet properties.
Use together with nitrates potentiates their antihypertensive activity. The result of such an effect may even be the death of the patient.
The combination of the drug with orally administered antidiabetic drugs, β-blockers and calcium channel blockers is also life-threatening.
Shelf life
Viagra can be used for a period of 24 months from the date of manufacture of the drug.
Application for children
The medication is not prescribed in pediatrics.
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Analogues
The drug's analogues are the substances Dzhenagra, Vekta and Potenciale with Penimex.
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Reviews
Viagra receives a large number of reviews from men of different ages. It is believed that the drug is highly effective, helping to improve sexual function. The only downside is that this drug is quite expensive.
Attention!
To simplify the perception of information, this instruction for use of the drug "Viagra" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.
Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.