How vardenafil works
Vardenafil is an active ingredient from the group of PDE-5 inhibitors with vasodilatory properties.
An erection occurs when the erectile tissue of the penis fills with blood during sexual arousal. Normally, there is little blood flow to them because the blood vessels are narrow – the smooth muscle cells in the vessel walls are tense.
During sexual arousal, however, nitric oxide (NO) is released first, which in turn increases the release of cGMP (cyclic guanosine monophosphate). This messenger substance ensures that the smooth muscles in the blood vessel walls relax. This causes the blood vessels to dilate, which significantly increases the blood supply to the erectile tissue – the penis hardens.
The enzyme phosphodiesterase 5 (PDE-5) ensures that the erection subsides. It is mainly found in the erectile tissue of the arterioles (tiny arteries) and breaks down the cGMP. This causes the erection to recede.
As a PDE-5 inhibitor, vardenafil blocks phosphodiesterase 5. The concentration of cGMP therefore increases, which strengthens or prolongs the erection.
Vardenafil only works during sexual stimulation.
Absorption, breakdown and excretion
When is vardenafil used?
Vardenafil is approved for the symptomatic treatment of erectile dysfunction (“impotence”) in male adults.
How vardenafil is used
It is usually recommended to take one tablet containing ten milligrams of vardenafil 25 to 60 minutes before sexual activity, irrespective of a meal. If necessary, the dose can be increased to a maximum of 20 milligrams or reduced to five milligrams.
Men of an older age should first try a five milligram dose.
The sexual enhancer should only be taken once a day.
What side effects does vardenafil have?
Vardenafil is a generally well-tolerated active ingredient. Possible side effects include headaches, reddening of the face (“flushing”), nasal congestion, dizziness and indigestion in the upper abdomen (dyspepsia). Some patients also experience color vision disorders.
Occasionally or rarely, PDE-5 inhibitors such as vardenafil cause side effects in the form of hypersensitivity reactions, eye pain and redness, vomiting, skin rash, priapism (painful permanent erection), palpitations, cardiac arrhythmia, heart attack and sudden cardiac death.
What should be considered when using vardenafil?
Contraindications
Vardenafil must not be taken if you:
- suffer from severe high blood pressure or severe liver failure (hepatic insufficiency)
- are being treated with nitrates or other so-called NO donors (such as molsidomine) (e.g. for angina pectoris = heart failure)
- have a specific eye disease (non-arteritic anterior ischemic optic neuropathy)
- are taking HIV protease inhibitors such as ritonavir or indinavir at the same time
- are taking riociguat at the same time (medication for certain forms of pulmonary hypertension)
- are over 75 years of age and are taking ketoconazole or itraconazole (antifungals) at the same time
Interactions
The use of the sexual enhancer can increase the effect of high blood pressure medication (antihypertensives).
If vardenafil is used together with so-called alpha blockers (alpha receptor blockers), the risk of side effects of the cardiovascular system and priapism (painful permanent erection) increases. Alpha blockers are used for benign prostate enlargement and high blood pressure.
Substances that inhibit a certain liver enzyme (CYP3A4) increase the concentration of vardenafil in the blood. This increases the risk of side effects. Such substances are, for example, ritonavir and saquinavir (against HIV), erythromycin and clarithromycin (antibiotics), itraconazole and ketocinazole (antifungals) and grapefruit juice.
Age restriction
Vardenafil is not indicated for use by persons under 18 years of age.
Pregnancy and breastfeeding
Vardenafil is not intended for the treatment of women.
How to obtain medication with vardenafil
Vardenafil is available from pharmacies in Germany, Austria and Switzerland in the form of orodispersible tablets or film-coated tablets on presentation of a doctor’s prescription.
