> ## Documentation Index > Fetch the complete documentation index at: https://docs.hi-doctor.ai/llms.txt > Use this file to discover all available pages before exploring further. # Vardenafil (Levitra) — how it works and dosing > Vardenafil for erectile dysfunction: how it works, EU authorisation history, trial results and reported side effects. Vardenafil is a prescription tablet for erectile dysfunction, authorised across the EU since 2003. It works the same way as sildenafil and tadalafil: it keeps the blood vessels in the penis relaxed so blood can flow in during sexual arousal. It must never be taken with nitrate heart medicines. ## What is vardenafil? Vardenafil is a PDE5-inhibitor tablet, film-coated or melt-in-the-mouth, for adult men with erectile dysfunction — the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. Sexual stimulation is still required for it to work. It is normally taken 25 to 60 minutes before sex, and it also comes as a tablet that dissolves on the tongue. Active ingredient: vardenafil. Dosages: 5, 10 or 20 mg, taken on demand. ## How it works Sexual stimulation makes nerves and blood vessel linings in the penis release nitric oxide, which switches on an enzyme called guanylate cyclase and builds up a messenger chemical called cyclic GMP in the erectile tissue. Cyclic GMP relaxes that smooth muscle, so arteries widen and blood flows into the corpus cavernosum. The body then steadily breaks the cyclic GMP down again. Vardenafil blocks the PDE5 enzyme that normally ends an erection, so the relaxation lasts and blood vessels stay filled during arousal. ## EU authorisation Levitra is centrally authorised, so a single EU authorisation covers all 27 member states. It was granted on 6 March 2003 and is held by Bayer AG in Germany. The 10 mg orodispersible tablet is taken without liquid and is a different presentation from the 10 mg film-coated tablet, not an interchangeable one. ## What the studies reported Every NCT identifier links to its ClinicalTrials.gov record. A readout is not the same as peer-reviewed publication. Results below are grouped by source and evidence grade so journal data and manufacturer figures are not confused. The EMA product information reports fixed-dose success rates: SEP2 (ability to penetrate) at 68% / 76% / 80% for 5 / 10 / 20 mg versus 49% on placebo, and SEP3 (ability to maintain an erection) at 53% / 63% / 65% versus 29% on placebo, measured over three months. The pivotal at-home trial was a single 12-week manufacturer-sponsored study in a mixed erectile-dysfunction population. The IIEF question-level changes are small point movements on a 5-point scale, not percentages, which is worth keeping in mind when comparing across different PDE5 inhibitor trials. * EMA EPAR — Levitra (vardenafil), EMEA/H/C/000475, marketing authorisation issued 06/03/2003 * EMA — Levitra EPAR product information (SmPC sections 4.2, 4.8, 5.1) * *Int J Impot Res* 2001 — first at-home clinical trial of vardenafil (PMID 11494074) * *J Androl* 2002 — vardenafil for treatment of men with erectile dysfunction: randomised, double-blind, placebo-controlled trial (PMID 12399521) ## What has been reported | Effect | Frequency in EU product information | Reported in at-home pivotal trial | | --------------------------------------------------------- | ----------------------------------- | --------------------------------- | | Headache | Very common (>1 in 10) | 7%–15% | | Flushing | Common | 10%–11% | | Dyspepsia or rhinitis | Common | Up to 7% | | Dizziness | Common (1 in 100 to 1 in 10) | — | | Visual disturbance, ocular hyperaemia, colour distortion | Uncommon (1 in 1,000 to 1 in 100) | — | | Non-arteritic anterior ischaemic optic neuropathy (NAION) | Not known | — | Vardenafil is contraindicated in men who have already lost vision in one eye from NAION. ## How to take it Vardenafil is taken 25 to 60 minutes before sexual activity. Light meals are fine, but very fatty meals delay onset. At most one dose is taken in 24 hours. The orodispersible tablet is placed on the tongue and dissolves without liquid — it is a different presentation from the film-coated tablet and is not interchangeable. ## Common questions Both are PDE5 inhibitors that work the same way. Vardenafil has high selectivity for the PDE5 enzyme. Some people who had side effects with sildenafil tolerate vardenafil well — the reviewing doctor weighs which PDE5 inhibitor fits your case best. Light meals are fine, but very fatty meals delay the onset of effect. Vardenafil is normally taken 25 to 60 minutes before sex regardless of meals. Vardenafil does not cause an erection on its own. Sexual stimulation is required for it to work, because the medicine only keeps the blood vessels relaxed once nitric oxide is released during arousal. Vardenafil is contraindicated in men with severe cardiovascular disease and in anyone taking nitrate medicines or nitric-oxide donors (poppers), because blood pressure can fall dangerously. The reviewing doctor screens cardiovascular history before prescribing. Yes. The 10 mg orodispersible tablet dissolves on the tongue without liquid. It is a different presentation from the 10 mg film-coated tablet and not an interchangeable one. ## Who it is not suitable for * Anyone taking nitrate medicines or nitric-oxide donors ("poppers") — blood pressure can fall dangerously * Men with severe cardiovascular disease Nitrates and poppers are contraindicated with vardenafil: taken together, blood pressure can fall dangerously. ## How Hi-Doctor handles it Some people who had side effects with sildenafil tolerate vardenafil well — the doctor weighs which PDE5 inhibitor fits your case best, after screening your cardiovascular history and current medicines. At most one dose is taken in 24 hours. See also [tadalafil](/library/medicines/tadalafil), [sildenafil](/library/medicines/sildenafil), and [avanafil (Spedra)](/library/medicines/spedra), another PDE5 inhibitor in the same group with a faster onset. For the full eligibility checks, see [safety](/essentials/safety) and [how a consultation works](/essentials/how-it-works). ## Start a consultation Answer the sexual health questionnaire and a registered doctor reviews it. They decide whether treatment is appropriate, which one, and at what dose — and declining is a normal outcome. See [what it costs](/essentials/pricing) and [how the review works](/essentials/how-it-works). This page is reference information, not medical advice and not a prescription. Whether a medicine is appropriate for you is decided by a registered doctor after reviewing your consultation.