Vardenafil Hydrochloride (3 brand names, 2 dosage forms, 1 route)
Available dosage forms: TABLET, ORALLY DISINTEGRATING, TABLET.
Routes of administration: ORAL.
Brand Names
- LEVITRA
- STAXYN
- VARDENAFIL HYDROCHLORIDE
Indications and Usage
Vardenafil hydrochloride tablets are indicated for the treatment of erectile dysfunction.
Warnings and Precautions
The evaluation of erectile dysfunction should include a medical assessment, a determination of potential underlying causes and the identification of appropriate treatment. Before prescribing vardenafil hydrochloride tablets, it is important to note the following:
Adverse Reactions
The following serious adverse reactions with the use of vardenafil hydrochloride tablets (vardenafil) are discussed elsewhere in the labeling: Cardiovascular Effects [see Contraindications (4.1) and Warnings and Precautions (5.1)] Priapism [see Warnings and Precautions (5.3)] Effects on Eye [see Warnings and Precautions (5.4)] Sudden Hearing Loss [see Warnings and Precautions (5.5)] QT Prolongation [see Warnings and Precautions (5.7)]
Mechanism of Action
Penile erection is a hemodynamic process initiated by the relaxation of smooth muscle in the corpus cavernosum and its associated arterioles. During sexual stimulation, nitric oxide is released from nerve endings and endothelial cells in the corpus cavernosum. Nitric oxide activates the enzyme guanylate cyclase resulting in increased synthesis of cyclic guanosine monophosphate (cGMP) in the smooth muscle cells of the corpus cavernosum. The cGMP in turn triggers smooth muscle relaxation, allowing increased blood flow into the penis, resulting in erection. The tissue concentration of cGMP is regulated by both the rates of synthesis and degradation via phosphodiesterases (PDEs). The most abundant PDE in the human corpus cavernosum is the cGMP-specific phosphodiesterase type 5 (PDE5); therefore, the inhibition of PDE5 enhances erectile function by increasing the amount of cGMP. Because sexual stimulation is required to initiate the local release of nitric oxide, the inhibition of PDE5 has no effect in the absence of sexual stimulation. In vitro studies have shown that vardenafil is a selective inhibitor of PDE5. The inhibitory effect of vardenafil is more selective on PDE5 than for other known phosphodiesterases (>15-fold relative to PDE6, >130-fold relative to PDE1, >300-fold relative to PDE11, and >1,000-fold relative to PDE2, 3, 4, 7, 8, 9, and 10).
Overdosage
The maximum dose of vardenafil hydrochloride tablets for which human data are available is a single 120 mg dose administered to healthy male volunteers. The majority of these subjects experienced reversible back pain/myalgia and/or “abnormal vision.” Single doses up to 80 mg vardenafil and multiple doses up to 40 mg vardenafil administered once daily over 4 weeks were tolerated without producing serious adverse side effects. When 40 mg of vardenafil was administered twice daily, cases of severe back pain were observed. No muscle or neurological toxicity was identified. In cases of overdose, standard supportive measures should be taken as required. Renal dialysis is not expected to accelerate clearance as vardenafil is highly bound to plasma proteins and not significantly eliminated in the urine.