Vardenafil

Vardenafil is an active ingredient from the group of PDE-5 inhibitors used to treat erectile dysfunction. Originally introduced by Bayer as the brand-name medication Levitra®, vardenafil has been available as a generic from various manufacturers since the patent expired.

The active ingredient is characterized by a rapid onset of action – in some men as early as 25 minutes. At 4-5 hours, its duration of action is comparable to that of sildenafil.

Vardenafil generics are subject to the same strict quality requirements as the original product and contain the identical active ingredient.

The medication is available as a film-coated tablet. Like all PDE-5 inhibitors, it only works with sexual stimulation – it does not produce an automatic erection.

Vardenafil belongs to the second generation of PDE-5 inhibitors. Its mechanism of action corresponds to that of other medications in this class:

The erection mechanism: During sexual arousal, nitric oxide (NO) is released in the penis. This activates the production of cGMP, a messenger substance that relaxes the blood vessels in the erectile tissue. More blood flows in, and an erection develops.

The role of vardenafil: The enzyme PDE-5 normally breaks down cGMP and ends the erection. Vardenafil selectively inhibits PDE-5, so that cGMP remains effective for longer. An erection can develop more easily and be maintained better.

Special features of vardenafil:

• High selectivity for PDE-5 – less effect on other PDE enzymes
• Rapid onset of action (often 25-30 minutes)
• Good efficacy even in patients with diabetes
• Fewer visual disturbances than with sildenafil

Important: Vardenafil does not work without sexual stimulation. The medication does not produce an automatic erection.

Vardenafil is suitable for adult men with erectile dysfunction of various causes:

Indications:

• Erectile disorders due to blood flow problems
• Erectile dysfunction in diabetes mellitus
• Psychologically caused erection problems
• Erectile disorders after prostate surgery (nerve-sparing)

Particularly suitable for:

• Men who want a rapid onset of action
• Patients with diabetes (good study results)
• Men who do not tolerate sildenafil optimally
• In case of intolerance to other PDE-5 inhibitors

Vardenafil vs. other PDE-5 inhibitors: Some men respond better to one active ingredient than to others. If sildenafil does not work optimally or causes side effects, vardenafil can be a good alternative.

Available dosages:

• 5 mg – Lowest dose, for certain patient groups
• 10 mg – Recommended starting dose
• 20 mg – If 10 mg is not effective enough

Dosage recommendations:

• Standard: 10 mg about 25-60 minutes before sexual intercourse
• If well tolerated: Increase to 20 mg possible
• In case of severe side effects: Reduction to 5 mg

Special patient groups:

• Men over 65: No routine adjustment needed
• Impaired liver function: Starting dose 5 mg
• Impaired kidney function: In case of severe impairment, starting dose 5 mg

Maximum dose: 20 mg per day, not more often than once daily

How to take:

• About 25 to 60 minutes before planned sexual intercourse
• With a glass of water
• Can be taken with or without food
• A meal with a moderate fat content has no significant effect

Onset of action: Vardenafil can start working after as little as 25 minutes – somewhat faster than sildenafil. In most men, the effect begins within 30-60 minutes.

Duration of action: The effect lasts about 4-5 hours. During this period, erections are possible with sexual stimulation.

Frequency: No more than one dose per 24 hours. Not intended for continuous daily use.

Alcohol: Moderate alcohol consumption is possible. Larger amounts can reduce effectiveness and increase side effects such as dizziness.

Absolute contraindications:

• Taking nitrates: Combining it with nitrates (nitroglycerin spray, isosorbide) or amyl nitrite (poppers) can cause a life-threatening drop in blood pressure.

• Severe heart disease: Heart attack within the last 6 months, unstable angina pectoris, severe heart failure, life-threatening cardiac arrhythmias

• Ritonavir/indinavir: HIV protease inhibitors strongly contraindicated

• Low blood pressure (below 90/50 mmHg)

• Severe liver disease

• Kidney failure requiring dialysis

• Hereditary retinal diseases (e.g. retinitis pigmentosa)

• Riociguat: Taking guanylate cyclase stimulators such as riociguat at the same time can lead to a symptomatic drop in blood pressure.

• Ketoconazole/itraconazole (taken by mouth): Concomitant use in men over 75 years of age

Use with caution in:

• Anatomical deformities of the penis
• Conditions with an increased risk of priapism
• Blood clotting disorders
• Congenital QT prolongation, hypokalemia or use of class IA (e.g. quinidine, procainamide) or class III (e.g. amiodarone, sotalol) antiarrhythmics: avoid vardenafil if possible

Common side effects (1-10%):

• Headache
• Facial redness (flushing)
• Stuffy nose
• Digestive problems
• Dizziness

Uncommon (0.1-1%):

• Nausea
• Increased sensitivity to light
• Blurred vision
• Watery eyes
• Muscle pain
• Back pain
• Increased intraocular pressure

Rare but serious:

• Priapism: Painful erection lasting more than 4 hours – see a doctor immediately
• Sudden loss of vision: Seek immediate medical evaluation
• Sudden hearing loss: See a doctor right away

In comparison: Vardenafil tends to cause fewer visual disturbances (blue-tinted vision) than sildenafil.

Absolutely contraindicated:

• Nitrates and NO donors: Life-threatening drop in blood pressure
• Guanylate cyclase stimulators such as riociguat: Possible symptomatic drop in blood pressure
• Ritonavir/indinavir: Extreme increase in vardenafil concentration
• Other HIV protease inhibitors: Also very strong CYP3A4 inhibitors

Important interactions:

• QT-prolonging antiarrhythmics (class IA, e.g. quinidine, procainamide; class III, e.g. amiodarone, sotalol): Avoid the combination if possible
• Alpha blockers: Increased lowering of blood pressure, 6-hour interval recommended
• CYP3A4 inhibitors: Avoid strong inhibitors such as ketoconazole or itraconazole (taken by mouth); ketoconazole and itraconazole contraindicated in men over 75 years of age; with erythromycin or clarithromycin, no more than 5 mg vardenafil
• Grapefruit juice: Can increase vardenafil levels
• Other PDE-5 inhibitors: Do not combine