Levitra does not directly cause penile erections but affects the response to sexual stimulation.

It is used to treat erectile dysfunction. It is also used (as off-label medicine) in adults for the treatment of Raynaud's phenomenon.

Vardenafil Dose in Adults

• Oral disintegrating tablets cannot be used interchangeably with film-coated tablets
• Patients who  require a dose other than 10 mg have to use  film-coated tablets.

Dosage in the treatment of Erectile dysfunction:

• Film-coated tablet (Levitra):
  • 10 mg orally given almost 1 hour before sexual activity.
  • Dosage varies from 5 to 20 mg
  • It is taken as one single dose and should not be taken more than once daily
  • The maximum dose is 20 mg in 24 hours
• The orally disintegrating tablet (Staxyn):
  • 10 mg given orally 1 hour before sexual activity.
  • The maximum dose is 10 mg in 24 hours

Off label dosage in the treatment of Raynaud phenomenon :

• It is given 10 mg orally twice daily.

Dosing adjustment with other medications:

• Alpha-blocker (Stable dose at the time of vardenafil initiation):
  • Film-coated tablet (Levitra):
  • Initially, 5 mg is given  once daily;
  • If an alpha-blocker is given in addition to vardenafil therapy, then it should be given at the smallest possible dose.
• Oral disintegrating tablet (Staxyn):
  • Do not use to start therapy.
  • Initially, therapy should be given with film-coated tablets at lower doses.
  • Patients who have been using previously filmcoated tablets then it may be switched to oral disintegrating tablets as recommended by a physician.
  • When coadministering, allow a time interval between dosing (eg, 6-hour interval).

• CYP3A4 inhibitors:

  • Film-coated tablet (Levitra):
  • The dosage of vardenafil can require adjustment in patients receiving potent CYP3A4 inhibitors (eg, clarithromycin, erythromycin, saquinavir, atazanavir, indinavir, itraconazole, ketoconazole, ritonavir ).
  • For ritonavir, maximum dose of vardenafil 2.5 mg should not be exceeded in a 72hour period.
  • For indinavir, atazanavir, ketoconazole, saquinavir,400 mg daily, itraconazole 400 mg daily, and clarithromycin, maximum dose of vardenafil 2.5 mg should not be exceeded in a 24-hour period.
  • For ketoconazole 200 mg daily, itraconazole 200 mg daily, and erythromycin, a single maximum dose of vardenafil 5 mg should not be exceeded in a 24-hour period.
  • Oral disintegrating tablet (Staxyn):
    • Donot coadminister  with potent or moderate CYP3A4 inhibitors (atazanavir, ritonavir,erythromycin, indinavir, clarithromycin, itraconazole, ketoconazole, , saquinavir)

Vardenafil Dose in Childrens

Not recommmended in children 

Pregnancy Risk Factor B

• Animal studies did not show any adverse events
• Vardenafil should not be used by women.
• In healthy males, there were no effects on sperm motility and morphology.

Vardenafil can be used during breastfeeding

• It is unknown whether vardenafil can be found in breast milk.

Vardenafil Dose in Kidney disease:

• Mild, moderate, or severe impairment:
  • No dosage adjustment advised.
• Hemodialysis:
  • Use is not advised.

Vardenafil Dose in Liver Disease:

• Mild impairment (Child-Pugh class A):
  • No dosage adjustment advised.
• Moderate impairment (Child-Pugh class B):
  • Film-coated tablet (Levitra):
    • Initially, 5 mg is given almost 60 minutes before sexual activity
    • The maximum dose is 10 mg daily which is taken as one single dose and should not be taken more than once daily
  • The orally disintegrating tablet (Staxyn):
    • Its use is not recommended.
• Severe impairment (Child-Pugh class C):
  • Use is not advised.

Common Side Effects of Vardenafil Include:

• Cardiovascular:
  • Flushing
• Central nervous system:
  • Headache

Less Common Side Effects of Vardenafil Include:

• Central Nervous System:
  • Dizziness
• Gastrointestinal:
  • Dyspepsia
  • Nausea
• Neuromuscular & Skeletal:
  • Back Pain
  • Increased Creatine Phosphokinase
• Respiratory:
  • Rhinitis
  • Flu-Like Symptoms
  • Nasal Congestion
  • Sinusitis

Contraindication to Vardenafil Include:

• Coadministration of nitric oxide donors or nitrates (either continuously and/or intermittently) or guanylate-cyclase stimulators, such as riociguat.
• Allergy reactions to vardenafil and any component of the formulation
• Indinavir, ketoconazole or ritonavir can be co-administered (Levitra and Staxyn), as well as erythromycin and clarithromycin.
• History of Pateritic Anterior Ischemic Optic Neuropathy (NAION)

Warnings and precautions

• Color discrimination:
  • It can lead to color discrimination impairment due to dose.
  • Patients with retinitis pigmentosa should use it with caution.
• Hearing loss:
  • It can lead to a sudden loss or decrease in hearing, tinnitus and dizziness.
• Hypotension
  • There have been decreases in blood pressure.
  • Patients with left ventricular obstruction should not use it.
  • Hypotension can be caused by coadministration of alpha-adrenergic antagonist treatment.
  • Before initiating treatment at the lowest dose, patients should be hemodynamically stable.
  • Reduce ethanol intake as it may increase the risk for symptomatic hypotension.
• Priapism
  • It has been reported that painful erections lasting more than six hours have been observed.
  • If the erection continues for more than four hours, advise patients to immediately seek medical attention.
  • Patients with conditions that may lead to priapism (multiple meeloma or sickle cell anemia) should be cautious.
• Vision loss:
  • Vision loss is a rare occurrence and can be a sign that NAION has been diagnosed.
  • If a sudden loss occurs in vision, advise patients to seek medical attention.
  • Other risk factors include smoking, hyperlipidemia and diabetes.
• Anatomical penis deformation:
  • Patients with anatomical deformations of the penis should be cautious.
• Bleeding disorders:
  • Patients with bleeding disorders should be treated carefully
• Cardiovascular disease
  • Patients with uncontrolled hypertension (>170/100mm Hg), hypotension (0-90/50mm Hg), life-threatening arrhythmias; stroke or MI within 6 months; heart disease or coronary artery disease causing angina are not recommended.
  • Patients with left ventricular obstruction should be careful.
  • Sexual activity can pose a cardiac risk so doctors may consider their patients' cardiovascular health before prescribing any treatment for erectile problems.
• Congenital QT prolongation:
  • Patients with congenital QT prolongation are not advised to use this product.
• Hepatic impairment
  • Patients with moderate hepatic impairment (Child Puugh class B) should be used with caution and dosage adjustment.
  • Patients with severe hepatic impairment (Child Pugh class C) are not advised to use this product.
• Peptic ulcer disease:
  • Patients with active peptic ulcer diseases should be cautious.
• Renal impairment
  • Patients with end-stage renal disease that requires dialysis are not advised to use it.

Vardenafil: Drug Interaction

Monitor:

Monitor for response, adverse reactions, blood pressure, and heart rate.

How to administer Vardenafil?

• It can be administered with or without food, about 60 minutes prior to sexual activity.
• The orally disintegrating tablet should not be removed from the pack until administered.
• While using dry hands, immediately place on the tongue.
• Then tablet will dissolve within seconds
• Do not use with liquids.
• Do not  split, crush or chew.

Mechanism of action of Vardenafil:

• It is a PDE-5 inhibitor.
• Although it does not cause penile erections, it affects sexual stimulation.
• The physiological mechanism for erection of penis involves the release of nitric dioxide in the corpus cavernosum and sexual stimulation.
• The Nitric oxide activates the guanylate cyclease, which causes an increase in cGMP. This results in smooth muscle relaxation, and blood flow to the corpus cavernosum.
• It also increases the NO effect by inhibiting phosphodiesterase 5
• Inhibiting PDE-5 with vardenafil causes local NO release.
• This results in increased levels of cGMP within the corpus cavernosum.
• It also leads to smooth muscle relaxation and an increase in blood flow to the corpus.
• It is safe to take at the recommended dosage.

Onset of action:  almost 60 minutes

Absorption: Rapid

Distribution: V : 208 L

Protein binding:  almost 95% (parent drug and metabolite)

Metabolism: Hepatic via CYP3A4 (major), CYP2C and 3A5 (minor); forms active metabolite

Bioavailability: almost 15%

• Film-coated tablet: Elderly (≥65 years): AUC increases by 52%;
• In hepatic impairment (moderate, Child-Pugh class B) AUC is increased by 160%
• Oral disintegrating tablet: Elderly (≥65 years): AUC is increased by 21% more compared to film coated tablet

Half-life elimination: Vardenafil and metabolite has half life of 4 to 6 hours

Time to peak plasma concentration: 0.5 to 2 hours

Excretion: In Feces (~91% to 95% as metabolites); in urine (~2% to 6%)   

International Brands of Vardenafil:

• APO-Vardenafil
• JAMP-Vardenafil
• JAMP-Vardenafil ODT
• Levitra
• MYLAN-VARDENAFIL
• Staxyn
• Levitra
• Levitra ODT
• Levitra Orodispersible
• Powerecta
• Romantigra
• Valenty
• Vardena
• Vivanza
• Yaila

Vardenafil Brands in Pakistan:

Levitra (Verdenafil) is not available in Pakistan.