This document discusses six alpha-adrenergic blockers: Tolazoline, Phentolamine Methylate, Phenoxybenzamine, Prazosine hydrochloride, Dihyroergotamine, and Methysergide. It provides the chemical structure and uses for each drug. Tolazoline is used to treat spasms of peripheral blood vessels. Phentolamine Methylate and Phenoxybenzamine are used for the control of hypertensive emergencies. Prazosine hydrochloride is used for the treatment of all types of hypertension. Dihyroergotamine and Methysergide are used for the treatment of migraine headaches.

1. RAJEEV GANDI COLLEGE OF PHARMACY BHOPAL (MP)
MEDICINAL CHEMISTRY -1ST
B.PHARMACY 4RTH SEM
UNIT-2ND
Submitted To Submitted By
Anuj sir Muni sahu

2. -:AIPHA ADRENERGIC BLOCKERS:-
(1) Tolazoline:- Chemically it is 2-Benzyl-2-
imidazoline monohydrochloride
It is recommended in Raynaud’s syndrome and
other condition involving peripheral vasopasm. It
is available as injection.
Uses- 1. Itis a vasodilator that is used to treat
spasms of peripheral blood vessels

3. (2) Phentolamine Methylate:- Phentolamine
methylate occurs as a white odourless, bitter
powder which is freely soluble in water.
It is prescribed to control or prevent hypertensive
episodes that occur in patient with
pheochromocytoma. It is also used in combination
with papaverine by intracavernosal injection in
impotence therapy.
Uses- 1. For the control of hypertensive
emergencies.

4. (3) Phenoxybenzamine:- Phenoxybenzamine HCL
is colourless crystalline compound soluble in
alcohol water and chloroform. It is used in the
treatment of peripheral vascular disease such as
Raynound’s syndrome and in the preoperative
management of patients with pheochromocytoma
whose tumors are not amenable to surgery.
N-
(2-chloroethyl)-N-(1-methyl-2-
phenoxyethyl)benzylamine
Use- 1. For the control of hypertensive
emergencies.
(4) Prazosine hydrochloride:- It is a quinazoline
derivative that has been found to be of value in

5. the management of hypertension. It is an Alpha-
adrenergic antagonist.It is administered orally.
Use- For the treatment of all types of
hypertension.
(5) Dihyroergotamine:- Dihyroergotamine is an
ergot alkaloid used to treat migraines. It is
believed to act upon serotonin receptors.

6. Use- 1. For treatment of migraine headache .
(6) Methysergide:- Methysergide is aprescription
drug used for prophylaxis of migraine headaches
and is sold under the the brand names. Sansert
and deseril in 2 mg dosages.

7. Use- 1. For treatment of headaches.