Vardenafil (Levitra) for Erectile Dysfunction — Libido & Sex
PDE5 inhibitor with the highest biochemical potency for PDE5, FDA-approved for erectile dysfunction.
Overview
Vardenafil is a potent PDE5 inhibitor with the highest in vitro selectivity for PDE5 of the three major PDE5 inhibitors (IC50 = 0.7 nM vs 3.5 nM for sildenafil and 6.7 nM for tadalafil). FDA-approved in 2003 for erectile dysfunction, vardenafil is available in both film-coated tablet form (Levitra) and an orodispersible tablet (Staxyn) that dissolves on the tongue without water. The pharmacokinetic profile is similar to sildenafil with a half-life of 4-5 hours and onset within 25-60 minutes. Clinical trials demonstrate efficacy rates of 65-80% across ED etiologies. Vardenafil's selectivity for PDE5 over PDE6 is 15-fold (better than sildenafil at 7-fold), resulting in fewer visual side effects. However, vardenafil has a notable QTc prolongation effect at supratherapeutic doses and is contraindicated with Class IA and III antiarrhythmics. The orodispersible formulation provides faster absorption and is not affected by food, offering a convenience advantage.
Indications
- FDA-approved: Erectile dysfunction
- Off-label: Premature ejaculation (limited evidence)
Mechanism of Action
Vardenafil binds to PDE5 with the highest affinity of the three major PDE5 inhibitors (IC50 = 0.7 nM)
Dosing
| Compound | Dose | Frequency | Notes |
|---|---|---|---|
| Vardenafil (tablet) | 10 mg | As needed, 25-60 min before activity | Standard starting dose |
| Vardenafil (tablet) | 5 mg | As needed | For patients >65 years or on moderate CYP3A4 inhibitors |
| Vardenafil (tablet) | 20 mg | As needed | Maximum dose |
| Vardenafil (Staxyn) | 10 mg | As needed | Orodispersible tablet — dissolves on tongue, not affected by food |
Evidence Grade
GRADE A
Safety & Contraindications
- Contraindicated with nitrates and riociguat
- Contraindicated with Class IA or III antiarrhythmics (QTc prolongation risk)
- Headache (15%), flushing (11%), rhinitis (9%), dyspepsia (4%)
- QTc prolongation at supratherapeutic doses — avoid in congenital QT syndrome
- Less visual disturbance than sildenafil (better PDE5/PDE6 selectivity)
- High-fat meals reduce absorption of film-coated tablets (not ODT)