This document discusses phosphodiesterase inhibitors, which were first isolated from rat brain in 1972 and inhibit the breakdown of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). It describes several subtypes of phosphodiesterase inhibitors, including non-selective inhibitors like caffeine and theophylline, as well as selective inhibitors of PDE1-5 that are used to treat conditions like erectile dysfunction, pulmonary arterial hypertension, chronic obstructive pulmonary disease, and intermittent claudication.

1. PHOSPHODIESTERASE
INHIBITORS

2. Introduction
• Isolated by UZONOV & WEISS in 1972 from
Rat Brain
• Therapeutic Action documented in 1977
• Inhibits Platelet Aggregation by promoting
hydrolysis and degradation of cAMP and / or
cGMP and release of Protein Kinase A

3. Subtypes
Non-Selective
CAFFEINE/THEOBROMINE/METHYLXANTHINES
AMINOPHYLLINE / THEOPHYLLINE (BDs)
PENTOXYFILLINE (Circulation enhancer DM / PVD)
PDE-1 Inhibitors
VINPOCETINE (Nootropic)

4. Subtypes
PDE-2 I
Erythro Hydroxy Nonyl Adenine (EHNA)
(Investigtive for CCF)
PDE-3 I
MILRINONE (Inotrope – CCF)
CILOSTAZOL (Arterial VD – Intermittent
Claudication)

5. Subtypes
PDE-4 I
MESEMBRINE (SRI)
ROFLUMILAST (COPD Exacerbations – FDA)
DROTAVERINE (Anti-spasmodic / Tocolytic)
Anti-inflamm / Anti-depressant

6. Subtypes
PDE-5 I (ED – degradation of cGMP in CC)
SILDENAFIL (VIAGRA) TADALAFIL (CIALIS) VARDENAFIL (LEVITRA)UDENAFIL
AVANAFIL
PAH
BPH / PAH t1/2
PE
tmax

7. Subtypes
PDE-10 I
PAPAVERINE (Papaver Somniferum)
Gastro-Intestinal Vasodilator
ED (Intracavernosal)
Coronary Vasodilator

8. THANK YOU