Diphenhydramine vs Sildenafil

## Diphenhydramine vs Sildenafil: Overview

This comparison examines the pharmacological differences between **Diphenhydramine** and **Sildenafil**.

## Mechanism of Action

**Diphenhydramine**: First-generation H1 antihistamine with anticholinergic properties.

**Sildenafil**: Selective PDE5 inhibitor increasing cGMP.

## Pharmacokinetics

**Half-life**: Diphenhydramine — 2-8 hours; Sildenafil — 4 hours.

## Chemical Properties

**Molecular Formula**: Diphenhydramine — C17H21NO; Sildenafil — C22H30N6O4S.

**Molecular Weight**: Diphenhydramine — 255.3550 g/mol; Sildenafil — 474.5800 g/mol.

**Type**: Diphenhydramine — Small molecule; Sildenafil — Small molecule.