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Generic Name: Vardenafil Hydrochloride
Class: Phosphodiesterase Type 5 Inhibitors
VA Class: GU900
Chemical Name: 1-[[3-(3,4-Dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f]-as-triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-4-ethylpiperazine
Molecular Formula: C23H32N6O4S
CAS Number: 224785-90-4

Introduction

Vasodilating agent; a selective phosphodiesterase (PDE) inhibitor.1

Uses for Levitra

Erectile Dysfunction (ED)

To facilitate attainment of a sexually functional erection in men with ED (impotence).1

Some experts recommend a selective PDE type 5 inhibitor as first-line therapy for ED unless contraindicated.40 Evidence currently insufficient to support superiority of one selective PDE type 5 inhibitor over another.40

Effective for ED only in the presence of adequate sexual stimulation.1

Levitra Dosage and Administration

Administration

Oral Administration

Administer orally, no more than once daily, without regard to meals.1 3

Administer approximately 1 hour before anticipated sexual activity.1

Dosage

Available as vardenafil hydrochloride; dosage expressed in terms of vardenafil.1

Adults

ED
Oral

Initially, 10 mg.1 Depending on effectiveness and tolerance, increase dosage to a maximum of 20 mg or decrease to 5 mg. Administer no more frequently than once daily.1

Prescribing Limits

Adults

ED
Oral

Maximum 20 mg daily.1

Special Populations

Hepatic Impairment

Oral

In patients with moderate hepatic impairment (Child-Pugh class B), decrease initial dosage to 5 mg; maximum dosage is 10 mg once daily.1

Do not use in patients with severe hepatic impairment (Child-Pugh class C).1

Renal Impairment

Oral

Dosage adjustments not required in patients with Clcr of 30–80 mL/minute.1

Do not use in patients requiring renal dialysis.1

Geriatric Patients

Oral

Reduce initial dose to 5 mg given no more frequently than once daily in men ≥65 years of age.1 26

Patients Receiving Concomitant Potent or Moderate CYP3A4 Inhibitors

Oral

Reduction in initial vardenafil dose required when given concomitantly with certain drugs that are potent or moderate CYP3A4 inhibitors.1 (See Specific Drugs or Foods under Interactions.)

Patients Receiving Concomitant α-Adrenergic Blocking Agents

Oral

In patients on stable α-adrenergic blocker therapy, initiate vardenafil at lowest recommended starting dose.1 Consider a time interval between dosing of vardenafil and concomitant α-adrenergic blocker.1 (See Specific Drugs or Foods under Interactions.)

Cautions for Levitra

Contraindications

  • Concomitant use of nitrates (either regularly or intermittently) or nitric oxide donors.1 28 (See Cardiovascular Effects under Cautions.)

  • Concomitant use of guanylate cyclase stimulators (e.g., riociguat).1

Warnings/Precautions

Sensitivity Reactions

Allergic reactions, including allergic edema and angioedema, reported.1

Patient Assessment

Thorough medical history and physical examination recommended to diagnose ED, determine potential underlying causes, and identify appropriate treatment.1 5

Review of the patient’s current drug regimens recommended to detect possible drug-induced ED.5

Cardiovascular Effects

Serious, potentially fatal cardiovascular events reported rarely.1 5 6

Potentiation of hypotensive effect with organic nitrates or nitric oxide donors (see Specific Drugs or Foods under Interactions) may result in life-threatening hypotension and/or hemodynamic compromise; concomitant use of such drugs with vardenafil contraindicated.1 28 (See Contraindications under Cautions.)

Sexual activity associated with a degree of cardiac risk; risk greater in men with pre-existing cardiovascular disease.1 5 6 28 Assess cardiovascular status of patient before initiating vardenafil therapy.1 28 Therapy for ED not recommended for men in whom sexual activity is inadvisable because of their underlying cardiovascular status.1 28

Safety and efficacy not established and use not recommended pending additional information in patients with unstable angina; hypotension (resting SBP <90 mm Hg) or uncontrolled hypertension (>170/110 mm Hg SBP/DBP); recent (within 6 months) stroke, life-threatening arrhythmia, or MI; or severe heart failure.1 4 7 8 26

Possible hypotension; consider whether patients with underlying cardiovascular disease could be affected adversely by vardenafil’s vasodilatory activity.1 Risk of an undesired hypotensive or vasodilatory response is of particular concern in patients with left-ventricular outflow obstruction (e.g., aortic stenosis, idiopathic hypertrophic subaortic stenosis).1 6

May prolong QT interval; consider such potential effects when prescribing vardenafil to patients with known history of QT prolongation or in those taking drugs known to prolong the QT interval.1 Avoid use of vardenafil in patients with congenital prolongation of the QT interval and in those receiving class IA or class III antiarrhythmic agents.1 (See Specific Drugs or Foods under Interactions.)

Concomitant Use with Potent or Moderate CYP3A4 Inhibitors

Increased plasma vardenafil concentrations with concomitant administration of potent (e.g., ritonavir, indinavir, ketoconazole) or moderate (e.g., erythromycin) CYP3A4 inhibitors; vardenafil dosage reduction recommended.1 29 30 31 33 34 47 48 49 50 51 (See Specific Drugs or Foods under Interactions.)

Data on specific interactions lacking, but increased exposure to vardenafil likely with other concomitant CYP3A4 inhibitors, including grapefruit juice.1

Safety of long-term concomitant use of vardenafil and HIV protease inhibitors not established.1

Priapism

Possible prolonged erections (>4 hours in duration) and priapism (painful erection >6 hours).1

May result in penile tissue damage and permanent loss of potency if priapism is not treated immediately.1 Use with caution in patients with conditions predisposing to priapism (e.g., sickle cell anemia, multiple myeloma, leukemia) and in patients with anatomical deformation of the penis (e.g., angulation, cavernosal fibrosis, Peyronie’s disease).1

Ocular Effects

Nonarteritic anterior ischemic optic neuropathy (NAION) reported rarely during postmarketing experience in temporal association with use of all PDE type 5 inhibitors.1 Potential increased risk of NAION recurrence in patients who have already experienced NAION.1 Use with caution in such patients and only if anticipated benefits outweigh risks.1 If sudden vision loss or decreased vision occurs, discontinue vardenafil and contact clinician immediately.1 28

Visual disturbances (e.g., abnormal, dim, or blurred vision; changes in color vision [e.g., chromatopsia]) reported.1 4

Not studied in patients with hereditary degenerative retinal disorders, including those with retinitis pigmentosa.1 Use not recommended in such patients until further information available.1

Otic Effects

Risk of sudden decrease or loss of hearing with all PDE type 5 inhibitors, in some cases accompanied by vestibular toxicity (e.g., tinnitus, vertigo, dizziness).1 28 41 44 Such effects reported rarely in clinical trials and during postmarketing experience.1 41 44 45 A causal relationship not established; however, a strong temporal association observed.1 28 41 44

Discontinue drug and contact clinician immediately if sudden decrease or loss of hearing occurs.1 28 44

Concomitant Administration with α-Adrenergic Blocking Agents

Use with caution in patients receiving α-adrenergic blocking agents; possible potentiation of hypotensive effects due to additive vasodilatory action.1 In some cases, dose adjustments are necessary; in other cases, concomitant administration not recommended.1 (See Specific Drugs or Foods under Interactions.) Safety of concomitant therapy also may be affected by intravascular volume depletion and use of other antihypertensive agents.1

Concomitant Use with Other PDE Type 5 Inhibitors or ED Therapies

Safety and efficacy of combined use with other PDE type 5 inhibitors or other treatments for ED not established; do not use vardenafil concomitantly with other PDE type 5 inhibitors.1

Hematologic Effects

No prolongation of bleeding time with vardenafil dosages ≤20 mg.1

However, data lacking on use in patients with bleeding disorders or active peptic ulcers;1 4 8 therefore, careful risk/benefit assessment is necessary before use in such patients.1 4 8

Specific Populations

Pregnancy

Category B.1 Not indicated for use in women.1

Lactation

Not indicated for use in women.1

Pediatric Use

Not indicated for use in pediatric patients; clinical trials not conducted in these patients.1

Geriatric Use

Safety and efficacy in males ≥65 years of age similar to that in younger males.1 Increased plasma vardenafil concentrations in men ≥65 years of age compared to that in younger males; therefore consider lower initial dosage.1 (See Geriatric Patients under Dosage and Administration.)

Hepatic Impairment

Decreased clearance in patients with mild (Child-Pugh class A) or moderate (Child-Pugh class B) hepatic impairment.1 (See Hepatic Impairment under Dosage and Administration.) Do not use in patients with severe hepatic impairment (Child-Pugh class C).1

Renal Impairment

Clearance decreased in patients with Clcr 30–80 mL/minute.1 (See Renal Impairment under Dosage and Administration.) Do not use in patients with end-stage renal disease requiring dialysis.1

Common Adverse Effects

Headache,1 2 7 8 flushing, 1 2 7 8 rhinitis,1 2 8 dyspepsia,1 2 7 sinusitis,1 flu syndrome,1 dizziness,1 increased creatinine kinase,1 nausea,1 back pain.1

Interactions for Levitra

Metabolized principally by CYP3A4; CYP2C and CYP3A5 appear to play a minor role.1

Drugs Affecting Hepatic Microsomal Enzymes

Inhibitors of CYP3A4: Potential pharmacokinetic interaction (increased plasma vardenafil concentrations).1

Specific Drugs or Foods

Drug

Interaction

Comments

α-Adrenergic blocking agents (e.g., alfuzosin, tamsulosin, terazosin)

Possible symptomatic hypotension 1

In patients on stable α-adrenergic blocker therapy, initiate vardenafil at lowest recommended starting dose1

In patients on optimized dose of vardenafil, initiate α-adrenergic blocker at lowest dose1

Alcohol

No potentiation of hypotensive effect reported1

Antacids (aluminum hydroxide and magnesium hydroxide)

Pharmacokinetic interaction unlikely1

Antiarrhythmic agents, class 1A (e.g., procainamide, quinidine) or class III (e.g., amiodarone, sotalol)

Possible prolongation of the QTc interval1

Avoid concomitant use1

Antihypertensive agents

Possible additive hypotensive effects

Antiretroviral agents, HIV protease inhibitors

Possible increased vardenafil concentrations and increased risk of vardenafil-associated adverse effects (e.g., hypotension, visual changes, prolonged erection)1 29 31 33

Decreased indinavir and ritonavir concentrations1 29 31 33

Ritonavir or lopinavir: Do not exceed a single vardenafil dose of 2.5 mg in 72 hours;1 29 no change in ritonavir dosage needed29

Ritonavir in combination with indinavir, atazanavir, saquinavir, fosamprenavir, or nelfinavir: Do not exceed a vardenafil dosage of 2.5 mg in 72 hours29 33

Nelfinavir, indinavir, amprenavir, saquinavir, fosamprenavir, or atazanavir: Use initial vardenafil dosage of 2.5 mg and do not exceed a single dose of 2.5 mg in 24 hours1 29 30 31 33

Monitor closely 29 31 33 34

Antiretroviral agents, nonnucleoside reverse transcriptase inhibitors

Possible increased vardenafil concentrations and increased risk of vardenafil-associated adverse effects (e.g., hypotension, visual changes, prolonged erection)29

Delavirdine: Use initial vardenafil dosage of 2.5 mg; do not exceed 2.5 mg once in 24 hours29

Aspirin

No increase in bleeding time reported1

Cimetidine

Pharmacokinetic interaction unlikely1

Digoxin

Pharmacokinetic interaction unlikely1

Erythromycin

Increased AUC and peak plasma concentrations of vardenafil1

Reduce initial vardenafil dosage to 5 mg in patients receiving erythromycin; do not exceed 5 mg of vardenafil once in 24 hours1

Glyburide

Pharmacokinetic interaction unlikely1

Grapefruit juice

Potential increase in vardenafil exposure1

Guanylate cyclase stimulators (e.g., riociguat)

PDE type 5 inhibitors may potentiate hypotensive effects of guanylate cyclase stimulators1

Concomitant use contraindicated1

Inhaled nitrites (e.g., amyl or butyl nitrite)

Potentiation of hypotensive effect28

Concomitant use contraindicated28

Itraconazole

Possible increased vardenafil concentrations1

Reduce initial vardenafil dosage to 2.5 mg in patients receiving itraconazole 400 mg daily; do not exceed 2.5 mg of vardenafil once in 24 hours1

Reduce initial vardenafil dosage to 5 mg in patients receiving itraconazole 200 mg daily; do not exceed 5 mg of vardenafil once in 24 hours1

Ketoconazole

Increased vardenafil concentrations 1

Reduce initial vardenafil dosage to 2.5 mg in patients in patients receiving ketoconazole 400 mg daily; do not exceed 2.5 mg of vardenafil once in 24 hours1

Reduce initial vardenafil dosage to 5 mg in patients receiving ketoconazole 200 mg daily; do not exceed 5 mg of vardenafil once in 24 hours1

Nifedipine

Possible additive hypotensive effect1

Nitrates and nitric acid donors

Potentiation of vasodilatory effects; potentially life-threatening hypotension and/or hemodynamic compromise can result1

Concomitant use contraindicated1 28

Ranitidine

Pharmacokinetic interaction unlikely

Warfarin

Pharmacokinetic and pharmacodynamic interaction unlikely1

Levitra Pharmacokinetics

Absorption

Bioavailability

Rapidly absorbed following oral administration; peak concentrations usually attained within 0.5–2 hours.1

Absolute bioavailability is approximately 15%.1

Food

Administration with a high-fat meal reduces the peak plasma concentrations by 18–50%.1 3

Distribution

Extent

Extensively distributed into tissues.1

Plasma Protein Binding

Approximately 95% for the drug and major metabolite.1

Elimination

Metabolism

Metabolized in the liver to active metabolite(s) principally via CYP3A4, with minor contributions from CYP3A5 and CYP2C.1

Elimination Route

Excreted as metabolites principally in the feces (91–95%) and to a lesser extent in urine (2–6%).1

Half-life

Terminal half-life 4–5 hours for drug and major metabolite.1

Special Populations

Clearance reduced in men ≥65 years of age, resulting in an increase in AUC and peak plasma concentrations compared with younger males.1

Clearance reduced in patients with moderate (Clcr of 30–50 mL/minute) or severe (Clcr <30 ml/minute) renal impairment, resulting in an increase in AUC compared with patients with normal renal function.1

Clearance reduced in patients with mild (Child-Pugh class A) or moderate (Child-Pugh class B) hepatic impairment, resulting in an increase in AUC and peak plasma concentrations compared with healthy adults.1

Stability

Storage

Oral

Tablets

25°C (may be exposed to 15–30°C).1

Actions

  • Selective inhibitor of phosphodiesterases (PDEs) with the greatest selectivity for PDE type 5, the principal isoenzyme involved in the metabolism of cGMP to GMP in the corpora cavernosa of the penis.1

  • Enhances the effect of nitric oxide by inhibiting PDE type 5-mediated hydrolysis of cGMP.1 2

  • Potentiates accumulation of cGMP only when cGMP production in the penis is increased by sexual arousal.1 No effect on erectile function in the absence of sexual stimulation.1

  • Modest peripheral vasodilation accompanied by a small increase in heart rate at usual dosages.1 6 27

  • Single oral doses of vardenafil 20 mg had no effect on sperm motility or morphology in healthy individuals.1

  • Although less affinity than sildenafil for PDE type 6 receptor in the retina, some transient visual abnormalities observed.1 27

Advice to Patients

  • Importance of instructing patients to read patient information prior to initiation of therapy and each time prescription is refilled.28

  • Importance of taking the drug exactly as prescribed and not exceeding recommended doses or frequency of use.28

  • Importance of sexual stimulation for the achievement of an erection with vardenafil therapy.1 28

  • Importance of informing clinician of any history of heart problems (e.g., angina, heart failure, arrhythmia, MI) prior to taking vardenafil; importance of not using vardenafil if underlying cardiovascular disease precludes sexual activity.1 28

  • Importance of informing clinician about presence of low or uncontrolled high BP, pulmonary hypertension, liver problems, kidney problems requiring dialysis, retinitis pigmentosa or history of severe vision loss, stomach ulcers, bleeding problems, deformed penis shape (e.g., Peyronie's disease), blood diseases (e.g., sickle cell anemia, multiple myeloma, leukemia), hearing problems, or a history of priapism, stroke, seizure, or QT-interval prolongation (long QT syndrome) prior to taking vardenafil.1 28

  • Importance of avoiding use of vardenafil if concurrently taking (regularly or intermittently) any form of organic nitrate and nitrite (e.g., nitroglycerin, isosorbide dinitrate) or nitric oxide donors (e.g., sodium nitroprusside), including recreational use of inhaled nitrites (“poppers”) such as amyl nitrate or butyl nitrate, because of the potential for sudden hypotension and associated dizziness, syncope, or even MI or stroke.1 26 28 (See Contraindications under Cautions.)

  • Importance of avoiding use of vardenafil if concurrently taking riociguat, a guanylate cyclase stimulator, because of the risk of potentiation of hypotensive effects.1 28 (See Contraindications under Cautions.)

  • Potential for sudden vision loss or decreased vision (i.e., nonarteritic ischemic optic neuropathy [NAION]).1 24 25 46 If NAION has occurred previously, possible increased risk of NAION recurrence.1 24 25 28 37 38 46 Importance of discontinuing vardenafil or other PDE type 5 inhibitors and seeking immediate medical attention if sudden vision loss or decreased vision occurs in one or both eyes.1 28 37 38 Possibility of visual disturbances (e.g., bluish tinge to objects, difficulty distinguishing between blue and green).1 28

  • Risk of sudden hearing impairment; advise patients to discontinue vardenafil and other PDE type 5 inhibitors and seek immediate medical attention if sudden hearing loss or decreased hearing occurs.1 28 41 44

  • Importance of informing patients of potential for interactions with concurrent potent or moderate inhibitors of CYP3A4 (e.g., ritonavir, ketoconazole, itraconazole, erythromycin).1 28 47 48 50 (See Specific Drugs or Foods under Interactions.)

  • Importance of contacting clinician or the emergency department if recommended dosage is exceeded.28

  • Importance of promptly informing clinician of adverse effects (e.g., hypotension, visual changes, syncope, priapism) that may occur during concomitant antiretroviral (e.g., ritonavir) therapy.47 48 50

  • Risk of symptomatic hypotension (e.g., dizziness, fainting) with concurrent use of α-adrenergic blocking agents or other antihypertensive agents; advise patient about appropriate countermeasures.1 (See Concomitant Administration with α-Adrenergic Blocking Agents under Cautions.)

  • Importance of not using other ED therapies during vardenafil therapy.1 28

  • Importance of seeking immediate medical attention if an erection persists longer than 4 hours or is painful.1

  • Advise patient of potential for transmission of sexually transmitted diseases (e.g., HIV) and the need to use protective measures to guard against transmission of such diseases.1 28

  • Importance of contacting a clinician for assessment of therapeutic benefit, the need for possible dosage adjustment, and potential adverse effects.1

  • Importance of informing clinician of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.1 28

  • Importance of informing patients of other important precautionary information.1 (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Vardenafil Hydrochloride

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Tablets, film-coated

2.5 mg (of vardenafil)

Levitra

GlaxoSmithKline

5 mg (of vardenafil)

Levitra

GlaxoSmithKline

10 mg (of vardenafil)

Levitra

GlaxoSmithKline

20 mg (of vardenafil)

Levitra

GlaxoSmithKline

AHFS DI Essentials. © Copyright 2017, Selected Revisions April 21, 2017. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

References

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3. Rajagopalan P, Mazzu A, Xia C et al. Effect of high-fat breakfast and moderate-fat evening meal on the pharmacokinetics of vardenafil, an oral phosphodiesterase-5 inhibitor for the treatment of erectile dysfunction. J Clin Pharmacol. 2003; 43(3):260-7. [PubMed 12638394]

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21. Sefetl AD. Phosphodiesterase type 5 inhibitor differentiation based on selectivity, pharmacokinetic, and efficacy profiles. Clin Cardiol. 2004; 27(Suppl. 1):I-14-9.

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25. Lilly. Cialis (tadalafil) tablets prescribing information. Indianapolis, IN; 2014 Apr.

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31. Bristol-Myers Squibb. Reyataz (atazanavir sulfate) prescribing information. Princeton, NJ; 2004 Jul.

33. GlaxoSmithKline. Lexiva (fosamprenavir calcium) tablets prescribing information. Research Triangle Park, NC; 2004 May.

34. Roche Laboratories. Invirase (saquinavir mesylate) capsules prescribing information. Nutley, NJ; 2004 Dec.

35. Goldstein I, Lue TF, Padma-Nathan H et al. Oral sildenafil in the treatment of erectile dysfunction. N Engl J Med. 1998; 338:1397-404. [PubMed 9580646]

36. Smith KM, Romanelli F. Recreational use and misuse of phosphodiesterase 5 inhibitors. J Am Pharm Assoc (Wash DC). 2005; 45(Jan-Feb):63-72.

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38. Food and Drug Administration. FDA statement: FDA updates labeling for viagra, cialis, levitra for rare postmarketing reports of eye problems. 2005 Jul. 8. From FDA website.

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41. Food and Drug Administration. Medwatch Safety-related drug labeling changes: Viagra (sildenafil), Cialis (tadalafil), Levitra (vardenafil) and Revatio (sildanafil) tablets [October 18 2007]. From FDA Website.

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45. Mukherjee B, Shivakumar T. A case of sensorineural deafness following ingestion of sildenafil. J Laryngol Otol. 2007; 121:395-7. [PubMed 17166328]

46. Bollinger KL, Lee MS. Recurrent visual field defect and ischemic optic neuropathy associated with tadalafil rechallenge. Arch Ophthalmol. 2005; 123:400-1. [PubMed 15767488]

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