Drug list Flashcards
Isoprenaline
Catecholamine (sympathomimetic)
Adrenaline & NA
Catecholamine (sympathomimetic)
Dopamine
Catecholamine (sympathomimetic)
Dobutamine
B1-adrenergic agonist (Direct acting Sympathomimetic)
Parenteral administration (catechol ring)
Acts directly & specifically on B1
Increase contractile force of heart - used in heart failure
Salbutamol
B2-adrenergic agonist (Direct acting Sympathomimetic)
Longer duration of action - no catechol nucleus
In high doses, also stim B1 receptors (less selective)
Orciprenaline
B2-adrenergic agonist (Direct acting Sympathomimetic)
Longer duration of action (3-4hrs) - no catechol nucleus, COMT does not act on it
In high doses, also stim B1 receptors (less selective)
Terbutaline
B2-adrenergic agonist (Direct acting Sympathomimetic)
B2 selective at therapeutic dose Resorcinol ring -> COMT not active Short acting Used for bronchospam Oral/Inhaled
Salmeterol
B2-adrenergic agonist (Direct acting Sympathomimetic)
B2 selective Long acting (12hr bronchodilatory) Inhalation
Formoterol
B2-adrenergic agonist (Direct acting Sympathomimetic)
B2 selective
Long acting (12hr bronchodilatory)
Inhalation
Faster onset of action (1-3 min) than sameterol (10-30min)
Phenylephrine
Indirect/Mixed action Sympathomimetic
Potent a-receptor action Min effects in heart & CNS Used for: - Vasoconstriction w/ LA - Decongestion (local vasoconstriction) - Shock dt impaired vasomotor activity - After MI / hypotension during spinal anaesthesia - Mydriasis & opthalmic decongestion
Ephedrine
Mixed action Sympathomimetic
Indirect action can cause tachyphylaxis Stimulating effect - also displaces NA Oral Reaches CNS - can suppress appetite Used for: - Vasoconstriction w/ LA - Asthma
Phenylpropanolamine
Indirect/Mixed action Sympathomimetic
Used for:
- Nasal decongestion
- Bronchodilation (less CNS stim than ephedrine)
Amphetamine
Indirect/Mixed Sympathomimetic
Primarily indirect (liberates NA from vesicles) Direct action in high doses Enters CNS - produce stimulation - anorexigenic effect - Habit forming (abuse potential) Used for: - Narcolepsy - Minimal brain dysfunction
Naphazoline
Incomplete Sympathomimetic
Little true sympathomimetic effects, apart from vasoconstriction
Used in nasal & eye drops
Oxymetazoline
Incomplete Sympathomimetic
Little true sympathomimetic effects, apart from vasoconstriction
Used in nasal & eye drops
Phenoxybenzamine
a-antagonist (Haloalkylamine)
Specific for a-receptors (a1»_space;» a2)
Covalent bond -> long acting
Non-equilibrium Competitive blocker
[high] also alkylate ACh & histamine receptors
Vasodilation (in blood vessels that are constricted under sympathetic influences)
i.e. Lowers systemic & pulmonary resistance
BUT
- Also blocks a2-receptors -> uncontrolled NA release
- Reflex increase in sympathetic stim of the heart via B-receptors -> Tachycardia
- Cause postural hypotension
Phentolamine
a-antagonist (Imidazoline)
Pure reversible competitive antagonist
Fast action, short duration
Selectivity a1=a2
Used for:
- Hypotension dt catecholamine tumours (Pheochormocytoma)
- Spasm & constriction of peripheral vasculature (Raynaud’s)
BUT:
Increases sympathomimetic B-activity –> Tachycardia
Postural hypotension
Prazosin
a-antagonist (Quinazoline)
Competitive reversible a1-receptor specific
- a2-receptors not affected
- No reflex tachycardia
Used for: Peripheral vasodilation
Not for essential HT:
- Short duration
- Cause 1st dose hypotension
- Tachyphylaxis
Labetolol
a- and B-antagonist
Lowers peripheral resistance via a-blocking
Prevents reflex tachycardia via B-blocking
Used for:
- Hypertensive crisis
- Produce controlled hypotension during surgery
- HT during 2nd half of pregnancy
- HT treatments after MI
Propranolol
B-antagonist
Not cardioselective (B1=B2)
Can precipitate bronchospasm in sensitive patients
No Intrinsic Sympathomimetic Activity
Timolol
B-antagonist
High potency
Not cardioselective
Little Intrinsic Sympathomimetic Activity
Pindolol
B-antagonist
(Partial agonist)
High potency
Not cardioselective
Intrinsic Sympathomimetic Activity
Metoprolol
B-antagonist
Cardioselective
No Intrinsic Sympathomimetic Activity
Atenolol
B-antagonist
Cardioselctive
No Intrinsic Sympathomimetic Activity
