Pharmacology summary notes

1
Pharmacology summary notes

• Unit 8

REB, 4MedStudents.com. 2003
2
Amino Acid Transmitter

• Excitatory Neurotransmitter Glutamate,
  Aspartate, Cysteic Acid, Homocysteic acid
• Inhibitory Neurotransmitter GABA, Glycine,
  Alanin, Taurine.
• GABA Agonist Muscimol
• GABA Antagonist Bicuculline
• GABA Modulator BDZ, Barbiturates, Steroids

Prof. Adem
3
Sympathomimetics

• Direct acting drugs
• Epinephrine
• Isoproterenol
• Phenylephrine

• Indirect acting drugs
• Amphetamine
• Tyramine

• Mixed acting drugs
• Ephedrine
• Metaraminol

Prof. Adem
4
a - Adrenergic Antagonist
Haloalkylamine derivatives Phenoxybenzamine Used
to treat pheochromocytoma
Imidazoline derivatives Phentolamine
Quinazoline derivatives Prazosin

• All a Antagonists are not selective to a1 or a2,
  except Prazosin which is selective to a1
• Therefore, all a Antagonists ( phenoxybenzamine
  Phentolamine) causes tachycardia postural
  hypotension. Except Prazosin has minimal side
  effects.

Prof. Adem
5
ß- Adrenergic Antagonist
Non Specific blocker ( a or ß) Labetalol Used for
hypertensive crisis with excess peripheral
resistance
Non Selective ß blocker (ß1 or ß2) Propranolol,
Timolol (used for chronic glaucoma)
Cardio-Selective Blocker (ß2 only) Atenolol (the
only ß blocker used for asthmatics
Partial Agonist Acebutolol, Pindolol ( has
intrinsic sympathomimetic effect
Prof. Adem
6
Cholinomimetics
Bethanechol
Carbachol
Pilocarpine Used for emergency glaucoma

• The drug that inhibit the transport of choline
  Hemicholinium
• The drug that inhibit the release of Ach
  Botulinum toxin
• The drug that induce the release of Ach Spider
  venum

Prof. Adem
7
Muscarinic Antagonists
Atropine Clinical usesA belladonna alkaloid,
antispasmodic agent, antidote for muscarinic
agonists (and idirect agonists as
acetylcholinesterase inhibitors) and
antisecretory agent. Side effects dry mouth,
tachycardia, blurred vision and constipation
Ipratropium
Scopolamine
Prof. Adem
8
Anticholinesterases
Prof. Adem
9
Choline Esterase Inhibitors
Dr.Petroianu

• Central Nervous System Syndrome
• Mad as a hatter
• Red as a beet
• Dry as a bone
• Blind as a bat
• Hot as a hear
• Physostigmine is used coz it is the only drug act
  CNS receptors

• Myasthenia
• Pryidostigmin Act on peripheral receptors

• Alzheimers Disease
• Tacrine
• Rivastigmine
• Donepezil
• Drug of choice
• less side effects
• Long duration

• Reversal NDMR
• Edrophonium
• Neostigmin
• Act on peripheral receptors

10
Non Depolarizing Muscle Relaxants
Dr.Petroianu
Intermediate, metabolized by Hoffmann degrd.
11
Depolarizing Muscle RelaxantsSUX

• SUX is the ultra-short acting muscle relaxant,
  and has a rapid onset of action.
• SUX is metabolized by AChE
• Side effects of using SUX
• Fasciculation
• Myalgia
• pressure(intracranial, intragastric,
  intraoccular)
• Similar to Ach ( Bronchospasm, Bradycardia)
• Hyperkalemia
• Masseter Muscle Spasm
• Malignant hyperthermia

Dr.Petroianu
12
Intravenous hypnotics
Dr.Petroianu
NMDA Antagonist Kitamine The only hyponotic that
have potent analgesic effect.
GABA Agonist BDZ ex. Medazolam Barbiturate ex.
Thiopental which induce release of
histamine. Propafol Etomidate which inhibit
steroid synthesis.
13
Inhaled Anesthetics
Dr.Petroianu
GABA Agonist Halothain metabolized by liver
causing hepatitis Enoflurain Isoflurain
Sevoflurain Desflurain no side effect but
lipid solubility therefore dose.
NMDA Antagonist Nitrous oxide
14
Drugs acting on Autonomic ganglia
Dr.Petroianu
Nicotine Non-selective
Trimethaphan Short acting Given I.V
Macamylamine Long acting Oral administration