Core Drugs Flashcards
Example of a ligand-gated ion channel
Nicotinic ACh receptor
Example of a G protein-coupled receptor
Muscarinic ACh receptor
Example of a kinase-linked receptor
Cytokine receptors
Example of a nuclear receptor
Oestrogen receptor
Nicotinic acetylcholine receptors
- Permeable to Na+, K+, Ca2+
- Nonspecific cation channel
- Expressed on the post-ganglionic neuronal cell in ANS
Describe neurotransmission (events at the synapse)
- Action potential travels down the presynaptic neuron —> calcium influx
- NTs carried in vesicles until they fuse with the membrane of presynaptic neuron —> released into synapse
- NTs bind to receptors on postsynaptic neuron until threshold is reached
- Excitation, action potential
Drugs that act as agonists at Nicotinic ACh receptors
Acetylcholine (full)
Nicotine (full)
Varenicline (partial - good sub for nicotine withdrawal)
What binds and activates adrenoreceptors
Adrenaline and noradrenaline
Example of a G-protein coupled receptor
Adrenoceptors
Adrenaline binding to a1 adrenoceptor
Vasoconstriction
Gq - activation of phospholipase C
Adrenaline binding to a2-adrenoceptor
Relaxation of GI tract
Presynaptic inhibition of noradrenaline in CNS
Gi - inhibition of adenylyl cyclase
Adrenaline binding to B1-adrenoceptor
Increased HR and cardiac muscle contraction
Gs - stimulation of adenylyl cyclase, increased cAMP)
Adrenaline binding to B2-adrenoceptor
Bronchodilation
Increased HR and cardiac muscle contraction
Gs - stimulation of adenylyl cyclase, increased cAMP)
Adrenaline binding to B3-adrenoceptor
Thermogenesis in skeletal muscle, lipolysis
Gs - stimulation of adenylyl cyclase, increased cAMP)
Adrenaline
Binds to ALL adrenoceptors
Full sympathetic physiological response
Isoprenaline
Binds to B1 and B2 adrenoceptors
Tachycardia and bronchodilation
Salbutamol
Binds to B2 adrenoceptors
Bronchodilation
Treats acute symptoms of asthma
Theophylline
Phosphodiesterase inhibitor (terminates action of cAMP)
Indicated for COPD
Example of a kinase-linked/enzyme-coupled receptor agonist
Insulin
Signalling cascade effects activated by insulin receptor
- Recruitment of glucose transporters
- Increased formation of glycogen
- Increased formation of fat
- Changes in gene expression
- Decreased glycogen to glucose conversion
- Increased formation of protein
What are Nuclear receptors
- Intracellular receptors (located in nucleus) bound by steroid hormones
- Hormone-receptor complex binds to DNA and affects gene transcription
What binds to nuclear receptors
Steroid hormones
Steroid hormones are …. and pass through plasma membrane to bind to …
Hydrophobic/lipophilic
Nuclear receptors
Receptor: androgen
Ligand:
Testosterone
Receptor : oestrogen
Ligand:
17beta- oestradiol
Receptor: glucocorticoid
Ligand:
Cortisol, corticosterone
Receptor: progesterone mineralocorticoid
Ligand:
Progesterone
Receptor: aldosterone receptor
Ligand:
Aldosterone
Aldosterone is secreted in response to …
Hyponatremia (low Na+ in blood) - causes resistance to thiazides
Thiazides
A type of diuretic — reduce fluid build-up in the body (lowers BP)
Condition: hypokalaemia
Low K+ levels in blood
Drug targets can be divided into 4 main categories:
Receptors
Enzymes
Ion channels
Carrier proteins
What is ibuprofen
An anti-inflammatory drug
Indication for ibuprofen
Pain and inflammation in rheumatic disease and musculoskeletal disorders
Mechanism of action for ibuprofen
Decreases blood flow by inhibition of prostaglandins (usually causes vasodilation)
Pharmacokinetics of ibuprofen
Half life = 1.2 - 2hrs
Liver disfunction = 3.1-3.4hrs
Side effects of ibuprofen
Irritation of GI tract
Impairment of renal function
What is amlodipine
Calcium channel blocker
Indication of amlodipine
Angina and hypertension
Pharmacokinetics of amlodipine
Long half life (40hrs)
Over 50hrs if renal disfunction
Side effects of amlodipine
Reduction in arterial BP
Reduction in smooth muscle contraction
NOT SUITABLE FOR EMERGENCY
What are selective serotonin re-uptake inhibitors (SSRIs) indicated for
Depression
Antagonist binds (blocks) serotonin receptors. More serotonin at synapse
Symptoms of SSRIs
MANY
Anxiety, weight changes, headache, arrhythmias, constipation, nausea etc…
Examples of SSRIs
Citalopram
Escitalopram
Fluoxetine
Fluvoxamine
Paroxetine
Sertraline
Sodium valproate
Treats epilepsy and bipolar disorder
Amitriptyline
(Tricyclic) Antidepressant
Side effects of amitriptyline
Sedation (H1 receptor blockage)
Dry mouth and constipation (mACh receptor blockage)
Pindolol
Treats hypertension
Partial agonist, Beta-blocker
Indicated for ventricular tachycardias, atrial fibrillation
Isoprenaline and propranolol bind to …..
The same B1-adrenoceptor
What does propranolol do
- Blocks adrenaline
- Activation of B1 results in reduction of HR and force of contraction
- Can also bind to B2
- t1/2 = 8hrs
Why does propranolol cause pharmacodynamic drug interaction
- Also has affinity for B2, blocks action of salbutamol
—> exacerbate symptoms for asthmatic patients
—> reduce effect of salbutamol
Aspirin
Anti-platelet drug (blood thinner) - Prevents blood clotting
Also used as a painkiller
Irreversible competitive antagonist
Atenolol
Beta-blocker used to treat angina and high BP
Low lipid solubility
Codeine
Used to relieve acute moderate pain
More basic than acidic
Paracetamol
Painkiller and used to treat fever
Bisoprolol
Beta blocker selective for B1
Treats hypertension, angina and heart failure
Dihydropyridine calcium channel blockers and examples
Decrease SVR and ABP
amlodipine and nicardipine
Nicardipine
Angina and hypertension
Digoxin
Arterial fibrillation + flutter, heart failure
Isosorbide dinitrate
Prophylaxis and angina
What are flecainide and propafenone examples of and indicated for
Sodium channel blockers
Arrhythmias
Amiodarone
Arrhythmias
Potassium channel blocker
What do calcium channel blockers do
Decrease myocardial contractility + electrical impulses
Examples of non-dihydropyridine and it’s indication
Verapamil, diltiazem
Prophylaxis + angina
ACE inhibitors function, indication, and name examples
Inhibit angiotensin I —> angiotensin II
Heart failure, hypertension
Ramipril, lisinopril, perindopril
Angiotensin receptor antagonist examples and indications
Losartan, candesartan, irbesartan
Hypertension
Beta blocker examples
Bisoprolol
Atenolol
Propranolol
Metoprolol
Carvedilol
Sotalol
Metoprolol
Hypertension treatment
Carvedilol
Hypertension treatment
Sotalol
Arrhythmias + arterial fibrillation
Example of loop diuretics and their indications
Furosemide, bumetanide
Oedema
Examples of thiazide/thiazide like diuretics
Bendroflumethiazide, indapamide, chlorthalidone
Bendroflumethiazide
Oedema
Indapamide
Hypertension
Chlorthalidone
Oedema, hypertension, heart failure
Warfarin
Anticoagulant - “blood thinner”
Prophylaxis and treatment of venous thrombosis and pulmonary embolism
Heparin
Anticoagulant - “blood thinner”
pulmonary embolism, unstable angina, DVT
Lidocaine
Arrhythmias, anaesthesia (nerve block)
Related to cocaine
Gaviscon and peptac are examples of … used for …
Antacids
Gastro-oesophageal reflux
Types of laxatives and their use
Bulk, osmotic, stimulant
Constipation
Loperamide
Diarrhoea, pain of bowel colic in palliative care
Proton pump inhibitor (PPI) examples and indications
Lansoprazole, omeprazole, prantoprazole
GI ulcer prevention/treatment, gastro-oesophageal reflux
Cimetidine
H2 receptor antagonist
GI ulcer prevention/treatment, gastro-oesophageal reflux
Gliclazide
Type 2 diabetes
Insulin
Type 1 and type 2 diabetes
Metformin
Type 1 and type 2 diabetes
Macrolides examples and indications
Clarithromycin, erythromycin
Penicillin alternative (antibiotic)
Penicillin examples
Amoxicillin, benzylpenicillin
Clotrimazole
Fungal/vaginal infections
