PDE5 Inhibitor Stack
Phosphodiesterase Type 5 Inhibitor Class
Overview
The PDE5 inhibitor class encompasses sildenafil tadalafil vardenafil and avanafil — a family of compounds that share the mechanism of inhibiting the PDE5 enzyme responsible for cGMP breakdown in vascular smooth muscle. This class represents the most clinically successful sexual health pharmacology in history with multiple FDA approvals and applications extending beyond erectile dysfunction into pulmonary hypertension heart failure muscle research and cancer biology. Understanding the class provides context for comparing individual agents and emerging peptide alternatives.
Mechanism of Action
All PDE5 inhibitors work by competitive inhibition of the PDE5 enzyme at its active site preventing the hydrolysis of cGMP. Their selectivity differences for PDE5 vs related PDE enzymes (PDE6 in retina PDE11 in testes and heart) explain class differences in side effects. Sildenafil has higher PDE6 affinity explaining visual side effects. Tadalafil has PDE11 activity explaining back pain and myalgia. The clinical differentiation between agents is primarily pharmacokinetic — onset duration and food interactions — rather than mechanistic. Emerging PDE5 research has revealed roles in cardiac muscle skeletal muscle cancer biology and neurological conditions that may expand therapeutic applications significantly beyond sexual dysfunction.
Dosage Information
Typical Dose
See individual agent entries
Frequency
See individual agent entries
Administration
Oral for all approved agents
Notes
Class overview entry. See Sildenafil or Tadalafil entries for specific dosing information.
Where does PDE5 Inhibitor Stack sit?
See how this peptide compares across all 111 peptides in our database.
Evidence Score
0.75
Potential Side Effects
Community Experiences
No experiences shared yet. Be the first!
Quick Facts
- Administration
- Oral for all approved agents
- Typical Dose
- See individual agent entries
- Frequency
- See individual agent entries
- References
- 0 curated + 45 from PubMed
- Clinical Trials
- 48 registered
- Evidence Score
- 0.7 / 100