Dosing and uses of Levitra, Staxyn ODT (vardenafil)
Adult dosage forms and strengths
tablet, film coated
- 2.5mg
- 5mg
- 10mg
- 20mg
tablet, orally disintegrating
- 10mg
Erectile Dysfunction
Film-coated tablet: 10 mg PO ~1 hour before sexual activity; may be increased to 20 mg or reduced to 5 mg, depending on effectiveness and tolerance; not to exceed 1 dose/day
Orally disintegrating tablet (ODT): 10 mg PO placed on tongue ~1 hour before sexual activity; not to exceed 1 dose/day
10-mg ODT not interchangeable with 10-mg film-coated tablet; ODT provides higher systemic exposure at same dose; if higher or lower doses are required, film-coated tablet should be prescribed
Dosing Considerations
Coadministration with strong CYP3A4 inhibitor
- Ketoconazole 200 mg/day or itraconazole 200 mg/day: Vardenafil dosage not to exceed 5 mg/day
- Ketoconazole 400 mg/day or itraconazole 400 mg/day: Vardenafil dosage not to exceed 2.5 mg/day
- Indinavir, saquinavir, atazanavir, or clarithromycin: Vardenafil dosage not to exceed 2.5 mg/day
- Ritonavir (600 mg q12hr): Vardenafil dosage not to exceed 2.5 mg/72 hr
Coadministration with moderate CYP3A4 inhibitor
- Erythromycin 500 mg q8hr: Vardenafil dosage not to exceed 5 mg/day
Coadministration with alpha blocker
- Stabilized on alpha-blocker therapy (eg, alfuzosin, terazosin, tamsulosin): 5 mg/day PO initially
- Stabilized on alpha-blocker therapy and taking moderate-to-strong CYP3A4 inhibitor: 2.5 mg/day PO initially
Dosing Modifications
Renal impairment
- Mild, moderate, severe impairment: Dosage adjustment not necessary
- Hemodialysis: Not recommended
Hepatic impairment
- Child-Pugh class A: Dosage adjustment not necessary
- Child-Pugh class B: Film-coated tablet, 5 mg PO ~1 hour before sexual activity; not to exceed 10 mg once daily; ODT not recommended
- Child-Pugh class C: Not recommended
Pediatric dosage forms and strengths
Not indicated
Geriatric dosage forms and strengths
Erectile Dysfunction
5 mg PO ~1 hour before sexual activity
AUC and Cmax increased by 39% and 21%, respectively, in elderly men (compared with men <45 years)
Levitra, Staxyn ODT (vardenafil) adverse (side) effects
>10%
Headache (15%)
Flushing (11%)
1-10%
Rhinitis (9%)
Dyspepsia (4%)
Flulike syndrome (3%)
Sinusitis (3%)
Back pain (2%)
Dizziness (2%)
Increased creatine phosphokinase (2%)
Nausea (2%)
<1%
Anaphylaxis
Angina
Insomnia
Myocardial infarction (MI)
Postural hypotension
Priapism
Pruritus
Rash
Warnings
Contraindications
Hypersensitivity
Soluble guanylate cyclase (sGC) stimulators (eg, riociguat); concomitant use can cause hypotension
Coadministration with nitrates
- Coadministration with nitrates (either regularly and/or intermittently) and nitric oxide donors
- Consistent with the effects of PDE5 inhibition on the nitric oxide/cyclic guanosine monophosphate pathway, PDE5 inhibitors may potentiate the hypotensive effects of nitrates
- A suitable time interval following PDE5 dosing for the safe administration of nitrates or nitric oxide donors has not been determined
Cautions
Anatomic deformation of penis, cardiovascular disease, left ventricular outflow obstruction, bleeding disorders, active peptic ulcer disease, liver disease, renal impairment, multidrug antihypertensive regimens, retinitis pigmentosa, conditions predisposing to priapism, concomitant use of CYP3A4 inhibitors
Avoid in patients with congenital QT prolongation or those taking class IA or III antiarrhythmics
Use in combination with other treatment for erectile dysfunction has not been studied and is not recommended
Not to be taken with other phosphodiesterase (PDE)-5 inhibitors (eg, sildenafil, tadalafil)
Concomitant use of alpha blockers increases risk of hypotension
May increase risk of rare sudden vision loss attributed to nonarteritic ischemic optic neuropathy; if vision problems arise, discontinue, and contact physician
Risk of sudden hearing loss
Pregnancy and lactation
Pregnancy category: B
Lactation: Unknown whether drug is distributed into breast milk; indicated for males
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Levitra, Staxyn ODT (vardenafil)
Mechanism of action
Sexual stimulation causes nitric oxide to be released in corpus cavernosum, and nitric oxide activates guanylate cyclase, which in turn increases cyclic guanosine monophosphate (cGMP), thus causing smooth-muscle relaxation; PDE-5 inhibitors enhance smooth muscle-relaxing effects of nitric oxide in corpus cavernosum by inhibiting degradation of cGMp
Absorption
Rapidly absorbed
Bioavailability: 15%
Onset: 60 min
Peak plasma time: 30-120 min
Peak plasma concentration: 8-19% lower for ODT than for film-coated tablet
Distribution
Protein bound: 95%
Vd: 208 L
Metabolism
Metabolized in liver by CYP3A4 and (in minor amounts) CYP2C9
Metabolites: M1 (active; plasma concentration 26% of parent compound)
Elimination
Half-life: 3-6 hr
Total body clearance: 56 L/hr
Excretion: Feces (95%), urine (5%)
Administration
Instructions
Oral tablet or orally disintegrating tablet
- Take about 60 minutes before sexual activity
- Maximum dosing frequency is one tablet per day
- May take with or without food
Orally disintegrating tablet
- Place on tongue where it will dissolve
- Do not swallow
- Take without liquid
