Vardenafil
Vardenafil is a selective PDE5 inhibitor used in adult men for erectile dysfunction. Its onset and effect window are similar to sildenafil, with a half-life of 4 to 5 hours. Marketed by Bayer as Levitra and as authorised generics.
- Chemical formula
- C23H32N6O4S
- CAS number
- 224785-91-5
- ATC code
- G04BE09
- Molecular weight
- 488.6 g/mol
- Drug class
- PDE5 inhibitor
- Also known as
- BAY 38-9456
What is it?
Vardenafil is a selective phosphodiesterase type 5 inhibitor approved in 2003 for the treatment of erectile dysfunction in adult men. It was developed by Bayer and ICOS Corporation under the code BAY 38-9456 and is marketed under the brand name Levitra. Vardenafil entered the market shortly after Cialis and offered a third PDE5 inhibitor option alongside sildenafil. Its pharmacological profile is broadly similar to sildenafil but with somewhat higher PDE5 selectivity and a slightly different metabolic pathway.
Mechanism of action
Vardenafil selectively inhibits PDE5, the enzyme that breaks down cyclic guanosine monophosphate in the corpus cavernosum. By blocking PDE5, the molecule allows cGMP — produced when nitric oxide is released during sexual stimulation — to accumulate. This relaxes the smooth muscle of penile arteries, increases blood flow and supports erection. According to comparative trials, vardenafil's PDE5 selectivity ratio is higher than sildenafil's, although the clinical relevance of this difference is debated.
Pharmacokinetics
After oral administration, vardenafil reaches peak plasma concentrations within approximately 30 to 120 minutes on an empty stomach. Bioavailability is about 15%, lower than sildenafil's 40%. The molecule is metabolised primarily by CYP3A4 to an active metabolite and is eliminated predominantly through the faeces. The terminal half-life is approximately 4 to 5 hours, supporting an effect window similar to sildenafil's. A high-fat meal can delay absorption by approximately one hour.
Indications
Vardenafil is approved in adult men for the treatment of erectile dysfunction. Unlike tadalafil, it is not approved for benign prostatic hyperplasia or pulmonary arterial hypertension. The compound is not approved for use in women, paediatric populations or as a recreational stimulant. According to the prescribing information, off-label use should be discussed with a qualified healthcare professional.
Safety profile
Common adverse effects in clinical trials include headache, facial flushing, nasal congestion, dyspepsia and dizziness. Visual disturbances are less frequent than with sildenafil but still occur. Serious but rare events include sudden hearing loss, priapism and QT-interval prolongation; the last has prompted caution in patients with congenital long-QT syndrome or those taking QT-prolonging drugs. The combination with organic nitrates is contraindicated. According to the manufacturer's prescribing information, anyone with cardiovascular disease, hepatic impairment or active medication therapy should consult a clinician before use.
Products containing this ingredient
Frequently asked questions
Is vardenafil more selective than sildenafil? ▾
In laboratory studies vardenafil shows higher PDE5 selectivity over related enzymes (PDE6, PDE11) than sildenafil. The clinical relevance of this difference is debated: vardenafil and sildenafil produce comparable rates of erectile response in head-to-head trials, although some patients report fewer visual side effects with vardenafil. According to comparative reviews, the choice between the two often comes down to individual response and tolerability rather than measured selectivity.
How is vardenafil different from tadalafil? ▾
Vardenafil and tadalafil are both PDE5 inhibitors but have very different pharmacokinetics. Vardenafil's half-life is 4 to 5 hours, supporting an effect window of up to four hours, similar to sildenafil. Tadalafil's half-life is approximately 17.5 hours, with an effect window of up to 36 hours. Tadalafil also has approved indications beyond ED (BPH, pulmonary arterial hypertension), while vardenafil is approved only for ED.
What dose of vardenafil should I start with? ▾
According to the prescribing information, the typical adult starting dose is 10mg taken approximately one hour before sexual activity. Depending on tolerability and response, the dose may be reduced to 5mg or increased to 20mg by the prescribing physician. The maximum dosing frequency is one tablet per 24 hours. A 2.5mg starting dose may be used in elderly patients or those taking interacting medications.
Does food affect vardenafil absorption? ▾
Yes, somewhat. A high-fat meal can delay onset of action by approximately one hour and slightly reduce peak plasma concentrations. According to the prescribing information, vardenafil is best taken on an empty stomach or after a light meal when a predictable onset is needed. Alcohol in moderate amounts is unlikely to alter the pharmacokinetics, but heavy intake may impair erectile response on its own.
What are the main contraindications for vardenafil? ▾
The most important contraindication is concurrent use of organic nitrates or guanylate cyclase stimulators, which can cause severe hypotension. Vardenafil is also contraindicated in patients with congenital long-QT syndrome and should be used with caution alongside class IA or III antiarrhythmics, due to the molecule's QT-prolonging effect. Severe hepatic impairment, recent stroke or heart attack, low blood pressure, severe cardiovascular disease and known hypersensitivity also require caution.
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.