Pharmacology Flashcards
1
Q
What is an irreversible side effect of tetracyclines?
A
Teeth staining
2
Q
How does montelukast work?
A
Blocks action of leukotriene D4 in the lungs which decreases inflammation and relaxes smooth muscle
3
Q
How does rituximab work and what conditions is it used for?
A
Binds to CD20 on B cells
Used in Hodgkins lymphoma and some vasculitides
4
Q
How does vigabatrin work?
A
Analogue of GABA which inhibits GABA aminotransferase (inhibits GABA breakdown)
Has a seizure suppression effect
5
Q
How does cyclophosphamide work?
A
Chemotherapeutic agent which causes cell apoptosis when it breaks down to its metabolite phosphoralide mustard
5
Q
Which chemotherapy agent has the side effect of haemorrhagic cyctitis?
A
Cyclophosphamide
6
Q
How does vincristine work?
A
Vinca alkaloid chemotherapeutic agent which acts through inhibiting microtubule activity
7
Q
Which chemotherapy drug causes peripheral neuropathy?
A
Vincristine
7
Q
How does doxorubicin work?
A
Anthracycline chemotherapy drug which acts through inhibition of topoisomerase II (allows uncoiling of DNA in preparation for transcription)
8
Q
Which chemotherapy agent is known to be cardiotoxic?
A
Doxorubicin
9
Q
How does blinatumomab work and what is it used for?
A
Targets the CD19 antigen on B-cells
Used in treatment of refractory B cell leukaemia
9
Q
Which biological agent works by inhibiting IgE?
A
Omalizumab
9
Q
How does inflixamab work?
A
Inhibits TNF-alpha
9
Q
Which type of antibiotic is known for its QTc prolongation?
A
Macrolides
10
Q
How do PPIs work?
A
Inhibit the H+-K+-ATP pump in the gastric parietal cells
11
Q
How does lamotrigine prevent seizures?
A
Prolongs sodium channel inactivation to prevent membrane depolarisation and subsequent seizure activity
12
Q
How does metformin work to lower blood sugars?
A
Decreased gluconeogenesis and increase peripheral utilisation of glucose
13
Q
How does insulin function to reduce blood sugar levels?
A
Enhances glucose uptake and cell metabolism
13
Q
How does gliclazide work to lower blood sugar levels?
A
Augments insulin secretion from functioning B pancreatic cells
13
Q
How does risperidone work?
A
It is a D2, 5-HT, alpha-1, histamine-1 antagonist
14
Q
How does a n oculogyric crisis present?
A
Involuntary deviation upward of both eyes
14
Q
Which type of drugs most commonly cause oculogyric crises?
A
Neuroleptic drugs
14
Q
What is the mechanism of action of trimethoprim?
A
Inhibits an essential step in synthesis of bacterial nucleic acid synthesis
Is an antifolate antibiotic
14
Q
What is the mechanism of action of gentamicin?
A
Inhibits bacterial synthesis by binding to 30s subunit of bacterial ribosomes
14
What is the mechanism of action of clarithromycin?
Inhibits bacterial synthesis by binding to 50s ribosomal subunit
14
What is the mechanism of action of cyclopentolate?
Muscarinic acetylcholine M1 receptor antagonist
15
What is the mechanism of action of azithromycin?
Binds to recombinant 23S rRNA of bacterial 50S ribosomal unit to inhibit bacterial synthesis
16
What is the mechanism of action of metronidazole?
Inhibits bacterial synthesis by causing loss of helical DNA structure and strand breakage
17
What is the mechanism of action of vancomycin?
Inhibits synthesis of bacterial cell wall via prevention of peptide incorporation into the peptidoglycan matrix
18
What is the mechanism of action of allopurinol?
Inhibits xanthine oxidase and its active metabolite
19
What is allopurinol used for in oncology patients?
Used to avoid TLS
20
What is the mechanism of action of amlodipine?
Inhibits calcium ion reflux at L-type calcium channels
21
What is the mechanism of action of hyoscine?
Antimuscarinic agent which competitively inhibits acetylcholine muscarinic receptors
22
What is the mechanism of action of isoprenaline?
Positive inotropic and chronotropic effects via B1 adrenergic stimulation
23
What is the mechanism of action of adrenaline?
Alpha and beta receptor agonist
B1 receptors - increases HR and myocardial contractility
A-adrenergic receptors - inhibits vasodilation
24
What is the mechanism of action of atenolol?
Selective B1 receptor antagonist - antagonist to sympathetic innervation
25
What is the mechanism of action of NAC?
Generates glutathione which in turn conjugates the NAPQI (paracetamol metabolite) into a harmless metabolite
Reduces the circulation of toxic metabolites
26
What is the mechanism of action of mycophenolate mofetil?
Prevents DNA synthesis and proliferation by inhibiting inosine monophosphate
27
What is the mechanism of action of flecainide?
Blocks sodium channels which reduce the rate of depolarisation of phase 0 without changing the overall AP duration.
28
What class of anti-arrythmic is flecainide?
Class Ic
29
Give an example of a class III antiarrhythmic drug?
Amiodarone
30
What is the mechanism of action of amiodarone?
Block potassium channels that increase the action potential duration by increasing length of repolarisation in phase 3.
31
What is an example of a class Ia anti-arrhythmic drug?
Disopyramide
32
What is the mechanism of action of disopyramide?
Block sodium channels that increase AP duration by increasing length of depolarisation during phase 0
33
What is the mechanism of action of Ivabradine?
Blocks the If channel in the SAN, reducing rate of pacemaker potential depolarisation, increasing refractory period and slowing the heart rate
34
What is an example of a class Ib anti-arrhythmic drug?
Mexiletine
35
What is the mechanism of action of melixetine?
Block sodium channels that shorten the AP duration by reducing the length of plateau in phase 2.
36
What is the most common side effect of IV quinine?
Tinnitus
37
What are the major side effects of ciclosporin?
Chronic interstitial nephritis
Hypertrichosis
Periodontal destruction
38
Which commonly used drug in TB management can reduce the effectiveness of warfarin?
Rifampicin - potent enzyme inducer
39
Which antibiotic can cause cholestatic jaundice?
Co-amoxiclav
40
Which chemotherapy agent can cause haemorrhagic cystitis?
Cyclophosphamide
41
What is the mechanism of action of fexofenadine?
H1 antagonist
42
What is the mechanism of action of fomepizole?
Competitive inhibitor of alcohol dehydrogenase
43
What is the mechanism of action of milrinone?
Positive inotrope - competitive phosphodiesterase-3-inhibitor that inhibits degradation of cAMP.
44
What is the mechanism of action of domperidone?
Dopamine-receptor antagonist
45
Which antiepileptic medication is associated with visual field defects?
Vigabatrin
46
What is the mechanism of action of aminophylline?
Inhibits phosphodiesterase type III and IV which breakdown cAMP in smooth muscle cells. Allows bronchodilation.
47
What is the mechanism of action of chloramphenicol?
Inhibits intracellular protein production
Binds to 50S subunit of 70S ribosome inhibiting action of peptidyl transferase
48
What is the mechanism of action for ondansetron?
Selective serotonin 5-HT3 receptor antagonist
49
What is the mechanism of action of verapamil?
Non-dihydropyridine CCB
50
What is the most common side effect of verapamil?
Constipation
51
What is the mechanism of action of infliximab?
IgG monoclonal ab which binds to TNF-alpha with high affinity
52
Which chemotherapeutic agent causes peripheral neuropathy?
Vincristine
53
Which drug causes "grey baby syndrome"?
Chloramphenicol
54
What is "grey baby syndrome"?
Cardiovascular collapse in infants due to immature hepatic glucuronidation meaning they are unable to excrete the drug.
55
Which corticosteroid has the highest mineralocorticoid activity?
Fludrocortisone
56
What is the mechanism of action of levetiracetam?
Binds to SV2A which regulates release of neurotransmitters into vesicles
57
What is a type A drug reaction?
"Augmented"
Exaggeration of a drugs normal pharmacological actions
Normally dose dependent
58
What is a type B drug reaction?
"Bizarre"
Novel response not expected from the known pharmacological actions of teh drug
59
What is a type C drug reaction?
"Continuing"
Persist for a very long time
60
What is a type D drug reaction?
"Delayed"
Become apparent sometime after the use of a medicine
61
What is a type E drug reaction?
"End-of-use"
Associated with medication withdrawal.
62
What is the mechanism of action of ondansteron?
Serotonin receptor antagonist - selectively blocks 5-HT3 serotonin receptor
63
What are the common side effects of ondansetron?
Dry mouth
Drowsiness
Constipation
64
Which antibiotic can cause red man syndrome if it is infused too quickly?
Vancomycin
65
How does red man syndrome present?
Pruritic erythematous rash over face, neck and upper torso
66
What is one of the main significant side effects of ethambutol?
Visual disturbances
67
What is the antidote for benzodiazepine overdose?
Flumazenil
68
What is the mechanism of action of prednisolone?
Inhibits migration of neutrophils
69
What is the mechanism of action of cyclizine?
Sedating antihistamine with antimuscarinic properties.
Acts on medulla oblongata
70
What is the mechanism of action of phenylephrine?
Pure alpha-adrenoreceptor agonis which elevates vascular resistance and increases BP
71
What is the mechanism of action of sildenafil?
Phosphodiesterase V inhibitor
72
What is the mechanism of action of insulin?
Translocation of pre-formed GLUT4 to the cell surface
73
What is nitric oxide often derived from?
L-arginine
74
What is the mechanism of action of nitric oxide?
Modulation of vascular tone via vasodilation
75
What is the mechanism of action of ursodeoxycholic acid?
Protects hepatocytes against bile-acid-induced apoptosis
76
What class of HIV drugs tend to cause lipoatrophy?
NRTIs (nucleoside reverse transcriptase inhibitors) e.g. zidovudine
76
What is the mechanism of action of indomethacin?
Inhibits prostaglandin E2 synthesis therefore closing the ductus arteriosus
77
What effects does adrenaline have in the treatment of anaphylaxis?
A1 receptor agonist - vasoconstriction
B1 agonist - increased contractility and HR
B2 agonist - bronchodilation
77
Which TB drug most commonly causes peripheral neuropathy?
Isoniazid
77
What is the preferred opioid used in syringe drivers?
Diamorphine - larger doses with smaller volumes compared to morphine
77
What is the mechanism of action of adenosine?
Blocks the AV node to allow normal heart rhythm to restart
Causes reversible bronchospasm
A1 adenosine-receptor agonist
77
What is the reason that ACEIs can cause cough as a side effect?
Bradykinin accumulates causing cough through bronchoconstriction
77
What is the conversion ration from oral morphine to subcutaneous diamorphine?
3mg PO morphine is roughly equivalent to 1mg S/cut diamorphine
77
What is the mechanism of action of ranitidine?
H2-receptor blocker
78
What is the antidote to unfractionated heparin?
Protamine
78
What renal complication can beta-lactam antibiotics sometimes cause?
Acute tubule-interstitial nephritis
78
What is the mechanism of action of sodium valproate?
Reduction of catabolism of GABA
79
What is the mechanism of action of isoniazid?
Inhibition of mycolic acid synthesis
79
What is the mechanism of action of lorazepam?
Activates chloride channels by binding in post-synaptic GABA-A ligand-gated chloride channels and increases flow of chloride ions into the cell
79
What is the ratio for converting IV to oral morphine?
1mg Iv morphine is roughly equivalent to 2mg PO morphine.
79
What is the mechanism of action of lidocaine?
Prolongs inactivation of voltage-gated sodium channels, which prevents action potentials from firing
79
What is the mechanism of action of morphine?
Adenylyl cyclase inhibitor
79
What treatment is used for malignant hyperthermia?
Dantrolene
79
What is the mechanism of action of sildenafil?
Phosphodiesterase V inhibitor - causes pulmonary-specific vasodilation and reduction of pressure
79
What antibiotics are more commonly known to cause erythema multiforme?
Sulphonamides (co-trimox) and penicillin
79
What is the mechanism of action of ipratropium?
Cholinergic receptor blocker - decreases smooth muscle contraction in the airways
79
What is the mechanism of action of furosemide?
Blocks sodium and chloride reabsorption in the loop of Henle
79
Which antibiotics can cause ototoxicity?
Gentamicin
Vancomycin
80
What is the mechanism of action of acetazolamide?
Reversible inhibitor of carbonic anhydrase
80
What is the mechanism of action of folic acid?
Activated by dihydrofolate reductase as it itself is biochemically inactive
80
What blood test should be closely monitored in ganciclovir treatment and why?
FBC as drug can cause leukopenia, neutropenia and thrombocytopenia
80
What is the mechanism of action of atomoxetine?
Activation of adrenergic alpha and beta receptors
Selective norepinephrine reuptake inhibitor
80
What is the main renal complication of acetazolamide therapy?
Acute interstitial nephritis
80
What is the mechanism of action of midazolam?
GABA-A receptor agonist
80
What is the first line treatment for CMV?
Ganciclovir
80
What is the mechanism of action of phenylephrine?
Alpha adrenergic effects - increases systemic vascular resistance via vasoconstriction with no effect on HR
80
What is the mechanism of action of chlorphenamine?
H1-receptor blocker
80
What is the mechanism of action of dornase alpha?
Endonucleic cleavage of extracellular DNA
80
What is the mechanism of action of LMWH?
Accelerates antithrombin-dependent inactivation of factor Xa
81
Which diuretic can cause a metabolic acidosis?
Acetazolamide
81
Why are statins and macrolides contraindicated to be taken at the same time?
Macrolides are potent CYP450 3A4 inhibitors and as statins are metabolised this way - may cause statin toxicity.
81
What is the mechanism of action of Ezetimibe?
Blocks the Niemann-Pick C1-like protein and therefore inhibits dietary cholesterol absorption
81
What is the drug metabolism pathway for carbamazepine?
CYP3A4
82
What is the mechanism of action of phenobarbital?
Increases opening time of chloride channels by binding to GABA-A receptors
82
What is the drug metabolism pathway for diazepam?
CYP3A4
82
What is the drug metabolism pathway for erythromycin?
CYP3A4
82
What is the drug metabolism pathway for fentanyl?
CYP3A4
82
What is the drug metabolism pathway for midazolam?
CYP3A4
82
What is the drug metabolism pathway for nifedipine?
CYP3A4
82
What is the drug metabolism pathway for ondansetron?
CYP3A4
83
What is the drug metabolism pathway for rifampicin?
CYP3A4
83
What is the drug metabolism pathway for caffeine?
CYP1A2
84
What is the drug metabolism pathway for theophylline?
CYP1A2
84
What is the drug metabolism pathway for phenytoin?
CYP2C9
84
What is the drug metabolism pathway for ibuprofen?
CYP2C9
84
What is the drug metabolism pathway for amitriptyline?
CYP2D6
84
What is the drug metabolism pathway for codeine?
CYP2D6
85
What is the drug metabolism pathway for SSRIs?
CYP2D6
85
What is the drug metabolism pathway for paracetamol?
Glucuronidation
86
What is the mechanism of action of mannitol?
Osmosis in the proximal renal tubule
87
Why should methotrexate and NSAIDs be avoided concurrently?
NSAIDs inhibit renal excretion of methotrexate
88
Which renal side effect is most common with topiramate?
Nephrolithiasis
89
How can trimethoprim affect U&Es?
As trimethoprim competes with creatinine for secretion into the renal tubule, it can cause asymptomatic elevation in creatinine with no change in urea. It is transient and resolves on cessation
90
What is the mechanism of action of atropine?
Blocks the vagal impulse
91
What is the mechanism of action of clindamycin?
Inhibits protein synthesis preventing elongation along peptide chain at the 50S ribosome
92
What respiratory complication occurs in upto 10% of patients taking long term amiodarone therapy?
Pulmonary fibrosis
93
What is the mechanism of action of caffeine?
Blocks adenosine receptors causing increased sensitivity to CO2 concentrations, resp centre stimulation and wakefulness
93
What is the mechanism of action of spironolactone in PCOS?
Antagonism of androgen receptors
94
Which antibiotic interacts with the OCP to decrease its effectiveness?
Rifampicin
95
Which receptors does low dose adrenaline primarily act upon?
Beta 1 ++
Beta 2 ++
96
What is the mechanism of action of desmopressin?
Water reabsorption activator - it is a synthetic analogue of ADH
Increases cellular permeability of collecting ducts resulting in water reabsorption
96
What is the mechanism of action of sulfasalazine?
Inhibits leukotrienes to reduce inflammation
97
What is the mechanism of action of alendronic acid?
Inhibits osteoclastic activity thereby increasing bone mass
98
Which fluid must amiodarone be administered in?
Glucose 5%
99
What is the mechanism of action of sumatriptan?
5HT-1D and 5HT-1B receptor agonist resulting in vasoconstriction of cranial blood vessels and inhibits release of pro-inflammatory neuropeptides
99
What is the mechanism of action of oxybutynin?
Muscarinic receptor antagonist - competitive antagonist of acetylcholine at postganglionic muscarinic receptors
100
Which receptors does high dose adrenaline primarily act upon?
Alpha 1 +++
Alpha 2 +++
Beta 1 +++
100
Which receptors does noradrenaline primarily act upon?
Alpha 1 ++++
Alpha 2 +++
Beta 1 +++
101
Which receptors does low dose dopamine primarily act upon?
Beta 1 ++
102
Which receptors does high dose dopamine primarily act upon?
Alpha 1 +++
Beta 1 +
103
Which receptors does dobutamine primarily act upon?
Beta 1 ++
104
What does low-dose adrenaline do to heart rate?
Increases
105
What does high-dose adrenaline do to heart rate?
Increases
106
What does noradrenaline do to heart rate?
Increases
106
What does low-dose dopamine do to heart rate?
Increases
106
What does high-dose dopamine do to heart rate?
Increases
107
What does low-dose dopamine do to Contractility?
Increases
107
What does dobutamine do to heart rate?
Increases
108
What does low-dose adrenaline do to Contractility?
Increases
108
What does high-dose adrenaline do to Contractility?
Increases
109
What does high-dose adrenaline do to SVR?
Increases
109
What does low-dose adrenaline do to Cardiac output?
Increases
109
What does low-dose dobutamine do to Contractility?
Increases
109
What does noradrenaline do to Contractility?
Increases
109
What does low-dose dopamine do to SVR?
Nil effect
110
What does low-dose dopamine do to Contractility?
Increases
110
What does low-dose adrenaline do to SVR?
Decreases
110
What does noradrenaline do to SVR?
Increases
110
What does high-dose adrenaline do to Cardiac output?
Nil effect
111
What does high-dose dopamine do to SVR?
Increases
111
What does dobutamine do to SVR?
Nil effect
111
What does noradrenaline do to Cardiac output?
Decreases
111
What does high-dose dopamine do to Cardiac output?
Decreases
111
What does low-dose dopamine do to Cardiac output?
Increases
111
What does dobutamine do to Cardiac output?
Increases
112
What are the side effects of prostaglandin E1?
Apnoea (most common)
Respiratory depression
Fever
Seizures
Tissue oedema
Cortical hyperostosis
112
What is the mechanism of action of terlipressin?
Vasopressin analogue
113
What can cimetidine do to U&Es?
Causes elevation of creatinine without changing GFR - potent inhibitor of tubular creatinine secretion
114
What is the mechanism of action of flucloxacillin?
Inhibits bacterial cell wall synthesis
115
What is the mechanism of action of methotrexate?
Dihydrofolate reductase antagonist
115
What is the mechanism of action of propranolol?
B1 and B2 receptor antagonist
115
What is the mechanism of action of adalimumab?
TNF-alpha inhibitor
116
How does a conjugate vaccine work?
Combines a weak polysaccharide antigen with a string protein antigen as a carrier so that a T cell response can be induced
117
Where is the site of action of furosemide?
Ascending loop of Henle
118
What is the starting dose (first bag) of NAC in a child >40kg?
150mg/kg in 200ml 5% glucose over 1 hour
119
What are the side effects of protease inhibitors?
Dyslipidaemia
Insulin resistance and diabetes
Fat accumulation
Lipodystrophy
120
