Pharmacology P1 Flashcards
1
Q
How does adrenaline work?
A
- sympathomimetic amine with both alpha and beta adrenergic stimulating properties
- acts on alpha 1 and 2 and beta 1 and 2 receptors
- beta 2 receptors in skeletal muscle caused vasodilation
- alpha receptors: inhibits insulin secretion by pancreas, stimulates glycogenolysis in liver and muscle and glycolysis in muscle
- beta receptors: stimulates glucagon secretion in pancreas, ACTH and lipolysis in adipose tissue
- increases cardiac output and total peripheral resistance
- causes vasoconstriction in skin and kidneys - narrow pulse pressure
2
Q
What are the indications, recommended doses and management of accidental injection of adrenaline?
A
- anaphlyaxis and cardiac arrest
- anaphylaxis: 0.5ml 1:1000 IM
- cardiac arrest: 10ml 1:10,000 IV or 1ml 1:1000 IV
- local infiltration phentolamine
3
Q
Acute withdrawal of alcohol:
A
Benzodiazepines
4
Q
Drugs to manage chronic alcoholism:
A
- disulfiram: promotes abstinence - severe reaction with alcohol due to inhibition of acetaldehyde dehydrogenase (CONTRA in IHD and psychosis)
- acamprosate: reduces craving, weak NMDA antagonist
5
Q
How does allopurinol work?
A
xanthine oxidase inhibitor
6
Q
How should allopurinol be initiated?
A
- initially 100mg od
- titrated every few weeks and aim serum uric acid <300 micro mol/L
- lower initial dose if reduced eGFR
- colchicine cover consider
7
Q
Indications allopurinol for gout:
A
- offer to all after first attack
- particularly if: more than 2 attack in a year, tophi, renal disease, uric acid renal stones, prophylaxis if on cytotoxics or diuretics, Lesch-Nyhan syndrome
8
Q
Adverse reactions allopurinol:
A
- severe cutaneous adverse reaction (SCAR)
- drug reaction with eosinophilia with systemic symptoms (DRESS)
- Steven-Johnson syndrome
9
Q
Interactions of allopurinol:
A
- azathioprine: xanthine oxidase converts 6-mercaptopurine to 6-thiouric acid, so high levels of mercaptopurine (reduce dose)
- cyclophosphamide: allopurinol reduces renal clearance - marrow toxicity
- theophylline: increased plasma concentration due to reduced breakdown
10
Q
Indications and side effects of alpha blockers:
A
- e.g. doxazosin, tamsulosin
- BPH, HTN
- ADR: postural hypotension, drowsiness, dyspnoea, cough
- CONTRA: cataract surgery (intra-operative floppy iris syndrome)
11
Q
Admiodarone induced thyrotoxicosis type 1:
A
- excess iodine-induced thyroid hormone synthesis
- goitre present
- manage with carbimazole or potassium perchlorate
12
Q
Amiodarone induced thyrotoxicosis type 2:
A
- amiodarone-related destructive thyroiditis
- absent goitre
- corticosteroids
13
Q
How can amiodarone cause hypothyroidism?
A
high iodine content - Wolf-Chaikoff effect (autoregulatory effect where thyroxine formation inhibited due to high levels of circulating iodide)
14
Q
Amiodarone adverse effects:
A
- thyroid dysfunction
- corneal deposits
- pulmonary fibrosis/pneumonitis
- liver fibrosis/hepatitis
- peripheral neuropathy/myopathy
- photosensitivity
- slate grey appearance
- thrombophlebitis and injection site reactions
- bradycardia
- lengthens QT interval
15
Q
Amiodarone drug interactions:
A
- reduced metabolism warfarin - increased INR
- increased digoxin levels
16
Q
How does aspirin work?
A
- blocks action of both cyclooxyrgenase-1 and 2
- cyclooxygenase responsible for PG, prostacyclin and thromboxane synthesis
- reduces platelet aggregation
- first line in patients with IHD
17
Q
What does aspirin potentiate and who should not take it?
A
- oral hypoglycaemics, warfarin, steroids
- not in children <16yo - Reye’s syndrome (with exception of Kawasaki disease)
18
Q
Features of beta-blocker overdose and management:
A
- bradycardia, hypotension, heart failure, syncope
- Atropine, glucagon
19
Q
What is botulinum toxin used for:
A
- blepharospasm
- hemifacial spasm
- focal spasticity including cerebral palsy, hand and wrist disability with stroke
- spasmodic torticollis
- severe hyperhidrosis of axillae
- achalasia
20
Q
Indications and ADR verapamil:
A
- angina, HTN, arrhythmias
- highly negatively inotropic with beta blockers (heart block)
- HF, constipation, hypotension, bradycardia, flushing
21
Q
Indications and ADR diltiazem:
A
- angina, HTN
- less negatively inotropic than verapamil but still not ideal with HF
- hypotension, bradycardia, HF and ankle swelling
22
Q
Indications and ADR nifedipine, amlodipine (dihydropyridines):
A
- HTN, angina, Raynaud’s
- affects peripheral vascular smooth muscle more than the myocardium, no worsening HF
- flushing, headache, ankle swelling
23
Q
Features of carbon monoxide toxicity:
A
- headache: 90%
- nausea and vomiting
- vertigo
- confusion
- subjective weakness
- severe toxicity: pink skin and mucosa, hyperpyrexia, arrhythmias, extrapyramidal features, coma, death
24
Q
Investigations CO poisoning:
A
- pulse oximetry may be falsely high due to similarities oxyhemoglobin
- venous or arterial blood gas
- <3% non smokers and <10% smokers
- > 30% severe toxicity
- ECG to look for cardiac ischaemia
25
Management CO poisoning:
- 100% high flow oxygen non-rebreather
- target 100%
- hyperbaric oxygen
26
How does ciclosporin work?
- immunosuppressant - decreases clonal proliferation of T cells by reducing IL-2 release
- binds to cyclophilin to form complex which inhibits calcineurin - activates transcription factors in T cells
27
ADR ciclosporin:
- nephrotoxicity
- hepatotoxicity
- fluid retention
- HTN
- hyperkalaemia
- hypertrichosis
- gingival hyperplasia
- tremor
- impaired glucose tolerance
- hyperlipidaemia
- increased susceptibility severe infection
28
Indications ciclosporin:
- organ transplant
- RA
- psoriasis
- UC
- pure red cell aplasia
29
MOA cocaine:
blocks dopamine, noradrenaline and serotonin uptake
30
ADR cocaine:
- CVS: coronary artery spasm (ischaemia and spasm), tachy and bradycardia, HTN, QRS widening, QT prolongation, aortic dissection
- neuro: seizures, mydriasis, hypertonia, hyperreflexia
- psychosis, agitation, hallucinations
- other: ischaemic colitis, hyperthermia, metabolic acidosis, rhabdomyolysis
31
Management cocaine toxicity:
- benzodiazepines
- chest pain: benzo + GTN
- HTN: benzo + sodium nitroprusside
32
Who should not take diclofenac:
- IHD
- peripheral arterial disease
- cerebrovascular disease
- congestive heart failure
33
How does digoxin work and how should you monitor it?
- decreases conduction through AV node which slows ventricular rate in AF and flutter
- increases force of cardiac muscle contraction due to Na/K ATPase inhibition
- stimulates vagus nerve
- narrow therapeutic index
- not monitored routinely
- in toxicity - digoxin concentrations should be measured within 8-12 hours of the last dose
34
Features of digoxin toxicity:
- generally unwell, lethargy, n&v, anorexia, confusion, yellow-green vision
- arrhythmias
- gynaecomastia
35
Precipitating factors digoxin toxicity:
- hypokalaemia
- increasing age
- renal failure
- myocardial ischaemia
- hypomagnesaemia, hypercalcaemia, hypernatraemia, acidosis
- hypoalbuminaemia
- hypothermia
- hypothyroidism
- drugs: amiodarone, quinidine, verapamil, diltiazem, spironolactone, circlosporin, thiazides and loop diuretics
36
Management of digoxin toxicity:
- digibind
- correct arrhythmias
- monitor potassium
37
Dopamine receptor agonist indications:
- Parkinson's
- prolactinoma/galactorrhoea
- cyclical breast disease
- acromegaly
38
Dopamine receptor agonist examples and ADR:
- bromocriptine, ropinirole, cabergoline, apomorphine
- ergot-derived associated with pulmonary, retroperitoneal and cardiac fibrosis
- ADR: nausea and vomiting, postural hypotension, hallucination, daytime somnolence
39
Drugs causing urticaria:
- aspirin
- penicillins
- NSAIDs
- opiates
40
Statin monitoring:
LFTs at baseline, 3 months and 12 months
41
ACEi monitoring:
U&E prior to treatment, after increasing and at least anually
42
Amiodarone monitoring:
- TFT, LFT , U&E prior
| - TFT, LFT every 6 months
43
Methotrexate monitoring:
FBC, LFT, U&E every 2-3 months
44
Azathioprine monitoring:
- FBC, LFT prior
- FBC weekly for first 4 weeks
- FBC, LFT every 3 months
45
Lithium monitoring:
- TFT, U&E prior
- Lithium levels weekly until stable, then every 3 months
- TFT, U&E every 6 months
46
Sodium valproate monitoring:
- LFT, FBC prior
| - LFT during first 6 months
47
Glitazone monitoring:
- LFT prior to treatment
| - LFT regularly during treatment
48
Drugs causing impaired glucose intolerance:
- thiazides, furosemide
- steroids
- tacrolimus, ciclosporin
- interferon-alpha
- nicotinic acid
- antipsychotics
- beta blockers slightly
49
Drugs causing thrombocytopenia:
- quinine
- abciximab
- NSAIDs
- diuretics: furosemide
- antibiotics: penicillins, sulphonamides, rifampicin
- carbamazepine, valproate
- heparin
50
Drugs causing urinary retention:
- TCA e.g. amitriptyline
- anticholinergics
- opioids
- NSAIDs
- disopyramide
51
Should aspirin be stopped before dental procedures?
no - continue to take anti-platelets as normal
