Methotrexate vs Sildenafil

## Methotrexate vs Sildenafil: Overview

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

## Mechanism of Action

**Methotrexate**: Dihydrofolate reductase inhibitor.

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

## Pharmacokinetics

**Half-life**: Methotrexate — 3-10 hours; Sildenafil — 4 hours.

## Chemical Properties

**Molecular Formula**: Methotrexate — C20H22N8O5; Sildenafil — C22H30N6O4S.

**Molecular Weight**: Methotrexate — 454.4400 g/mol; Sildenafil — 474.5800 g/mol.

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