1. Associate Professor in Pharmacology,
AUTACOIDS
Dr A. Shyam Sundar,
Associate Professor in Pharmacology,
University of Nizwa,
Sultanate of Oman

2. UNIT 9: Autacoid Pharmacology
UNIT INSTRUCTIONAL OUTCOMES:
At the end of this unit, the student should be able to,
List names of autacoids of pharmacological interest
State vital information about the drugs act by modifying autacoids
Apply pharmacological knowledge gained in the clinical scenario.

3. Overview
Autacoids are local hormones which are produced locally, exert their
actions locally and degraded locally.
They can be derivatives of
1. Amines (Histamine and Serotonin).
2. Peptides (Bradykinin,Angiotensin).
3. Lipids (Prostaglandins, Leukotrienes and Platelet activating factor)
Histamine , Serotonin will be discussed in detail in this lecture.
We have already discussed the actions of Angiotensin in the chapter
anti-hypertensive drugs and Leukotrienes were discussed during
anti asthmatic lectures.

4. HISTAMINE- RECEPTORS LOCATION AND ACTIONS
Lippincott's Illustrated Reviews: Pharmacology, 4th Edition.

5. HISTAMINE RECEPTOR BLOCKERS AND THEIR CLINICAL USES
H1 receptor blockers:
First generation:
Azelastine
Chlorpheniramine
cyproheptadine
Diphenhydramine
Hydroxyzine
Phenindamine
Promethazine
Tripelenamine
Second generation :
Cetirizine
Desoratadine
Fexofenadine
Loratadine
Clinical uses of H1 receptor blockers
Urticaria
Hypersensitivity reactions
Hypersensitive reactions:
An inappropriate and excessive reaction to an allergen (as pollen or dust or animal hair or certain foods); severity ranges from mild allergy to severe systemic reactions leading to anaphylactic shock
Urticaria:
An itchy skin eruption…
Anand, M.D. Ramachandran, Pharmacology Recall, Second Edition, Wolters Kluwer

6. ADRs of H1 antagonists Vertigo: A sensation of dizziness
Drowsiness: Dull with sleepiness
Dizziness: Having a whirling(to rotate/spin) sensation and tendency to fall
Lippincott's Illustrated Reviews: Pharmacology, 4th Edition.

7. HISTAMINE RECEPTOR BLOCKERS AND THEIR CLINICAL USES
Peptic Ulcer
Zollinger-Ellison Syndrome
Acute Stress ulcers
Gastroesophagal reflex disease
Lippincott's Illustrated Reviews: Pharmacology, 4th Edition.

8. SEROTONIN
Serotonin is an indole ethylamine found in both plant and animal tissues.
90% of serotonin is present in GI tract and 10% present in CNS.
Serotonin exert its action through seven major 5-HT cell membrane receptor subtypes.
Physiological actions of Serotonin:
Anand, M.D. Ramachandran, Pharmacology Recall, Second Edition, Wolters Kluwer

9. Sumatriptan is a serotonin agonist used to treat migraine headaches.
Dizziness, Neck pain and muscle weakness are the
adverse effects of sumatriptan.
SEROTONIN ANTAGONISTS AND THEIR CLINICAL USES
Anand, M.D. Ramachandran, Pharmacology Recall, Second Edition, Wolters Kluwer

10. PROSTAGLANDINS Therapeutic Uses of Prostaglandins: Impotence
Several of the naturally occurring prostaglandins, such
as dinoprost , dinoprostone , and carboprost , find use as
abortifacients . Misoprostol in combination with methotrexate is
particularly effective in terminating pregancy in the first trimester.
Misoprostol is a synthetic prostaglandin E1 analog used to inhibit
the secretion of hydrochloric acid in the stomach. It produces
inhibition of gastric acid and pepsin secretion and enhances
mucosal resistance to injury. Misoprostol is particularly useful in
patients with gastric ulcer who are chronically taking nonsteroidal
anti-inflammatory agents
Therapeutic Uses of Prostaglandins:
Alprostadil injected into the corpus cavernosum of
the penis provides effective treatment of some forms
of male impotence.
Impotence
Anand, M.D. Ramachandran, Pharmacology Recall, Second Edition, Wolters Kluwer