Vigorex Tablet 50mg

Description

Indications
Vigorex is used for the treatment of erectile dysfunction (ED) in men, which is characterized by the inability to achieve or sustain an erection sufficient for satisfactory sexual performance. Sexual stimulation is necessary for Vigorex to be effective. It is also indicated for managing pulmonary arterial hypertension.
Take the medication as prescribed by a registered healthcare professional.

Description
Vigorex is a selective, reversible inhibitor of the enzyme phosphodiesterase type 5 (PDE5), which specifically degrades cyclic guanosine monophosphate (cGMP). When sexual stimulation occurs, it causes the release of nitric oxide, which inhibits PDE5, leading to higher cGMP levels in the corpus cavernosum of the penis. This results in the relaxation of smooth muscle and enhanced blood flow into the penile tissues, facilitating an erection. Vigorex does not have an effect in the absence of sexual stimulation.

Pharmacology

• Mechanism of Action:
  The physiological process of achieving an erection involves the release of nitric oxide (NO) in the corpus cavernosum during sexual activity. NO activates guanylate cyclase, increasing the production of cGMP. This promotes smooth muscle relaxation and increases blood flow to the penis. Sildenafil, the active component in Vigorex, enhances the effect of NO by inhibiting PDE5, preventing the breakdown of cGMP, and supporting an erection during sexual stimulation.
• Pharmacokinetics and Metabolism:
  Sildenafil is rapidly absorbed after oral intake, with an average bioavailability of 41%. The drug is primarily metabolized in the liver through cytochrome P450 3A4, resulting in an active metabolite similar to sildenafil. The elimination half-life of both sildenafil and its metabolite is about 4 hours.
• Absorption and Distribution:
  Sildenafil reaches peak plasma concentrations between 30 to 120 minutes after ingestion in a fasted state. Food, particularly a high-fat meal, may slow its absorption rate.
• Excretion:
  The majority of sildenafil is excreted in the feces (approximately 80%), with the remaining 13% excreted in urine.

Dosage & Administration

• For Erectile Dysfunction:
  For most patients, the recommended dose is 50 mg, taken approximately one hour before sexual activity. Sildenafil can be taken anywhere between four hours and half an hour before activity. The dose may be adjusted to a maximum of 100 mg or reduced to 25 mg, depending on effectiveness and tolerance. The maximum frequency is once daily.
• For Pulmonary Arterial Hypertension:
  The recommended dose is 20 mg, taken three times daily at intervals of 4 to 6 hours, with or without food.
  Consult a registered healthcare professional before use.

Interaction
Vigorex is metabolized primarily by CYP3A4 and to a lesser extent by CYP2C9. Co-administration with inhibitors of these enzymes, such as ketoconazole, erythromycin, or HIV protease inhibitors, can increase the plasma concentration of Vigorex. Conversely, CYP3A4 inducers like rifampin may lower its plasma levels. Vigorex’s interaction with other medications, particularly those affecting blood pressure or involving the liver enzymes, should be carefully managed.

Contraindications
Vigorex should not be used by patients with hypersensitivity to any of its components. It is contraindicated for use in patients taking organic nitrates, as it may amplify their blood pressure-lowering effects.

Side Effects
Common side effects may include dizziness, headache, facial flushing, and digestive issues like indigestion or nausea. More severe reactions, such as priapism (prolonged erection), vision changes, and cardiovascular events, have been reported. Patients should seek immediate medical help if any serious side effects occur.

Pregnancy & Lactation
Vigorex is not indicated for women and should not be used during pregnancy. Animal studies show no teratogenic or embryotoxic effects, but the drug’s effects in pregnant women are not well-studied.

Precautions & Warnings
Patients with cardiovascular conditions or those who have experienced a recent heart attack, stroke, or arrhythmia should exercise caution when using Vigorex. It is essential for individuals with preexisting health conditions like hypertension, heart disease, or bleeding disorders to be closely monitored.
A prolonged erection lasting more than 4 hours requires immediate medical attention to avoid permanent damage.

Overdose Effects
In the case of an overdose, standard supportive measures should be followed. Vigorex is highly protein-bound and is not significantly eliminated through renal dialysis.

Therapeutic Class
Drugs for Erectile Dysfunction

Storage Conditions
Store Vigorex in a dry place, away from light and heat. Keep it out of reach of children.