Adverse drug reactions

Question 1

nephrogenic diabetes insipidus

a. data interpretation (blood)
b. drugs causing (4)

Answer 1

a. low Na;
b. Demeclocycline (abx for lyme disease, acne, bronchitis); Lithium; effervecent/IV preparations with high Na; excess IV saline

Question 2

Drug causing high neutrophils

Answer 2

Steroid

Question 3

Drugs causing low neutrophils (2)

Answer 3

Clozapine (anti-psychotic)

Carbimazole (anti-thyroid)

Question 4

Drugs causing hyponatraemia (1)

Answer 4

Diuretics (any)

hypovolaemic

Question 5

Drugs causing hypokalaemia (2)

Answer 5

Loop diuretics

thiazide diuretics

Question 6

Drugs causing hyperkalaemia (6)

Answer 6

1- Potasium sparing diuretics (spironolactone)
2- ACE inhibitors
3- Angiotensin II receptor blockers
4- ciclosporin
5- amiloride

ACE inhibitors

Question 7

How do ACE inhibitors or NSAIDs cause pre-renal AKI?

Answer 7

can trigger renal artery stenosis = hypoperfused kidneys

Question 8

Drugs causing intrinsic AKI (4)

Answer 8

Nephrotoxic abx (gentamycin, vancomycin and tetracyclines)
ACE inhibitors
NSAIDs
IV contrast

Question 9

Hepatitis/cirrhosis

a. data interpretation (blood)
b. drugs causing this(3)

Answer 9

a. raised bilirubin + raised AST/ALT = hepatocellular damage
b. Paracetamol overdose
Statins
Rifampicin

Question 10

Cholestasis

a. data interpretation (blood)
b. drugs causing this (5)

Answer 10

a. raised bilirubin + raised ALP = obstructive damage
b.
Flucloxacillin
Co-amoxiclav
nitrofurantoin
Steroids
Sulphonylureas

Question 11

hyperkalaemia on ECG

Answer 11

Tall tented T waves

• height >2/3 of QRS
• all leads

Question 12

Drugs causing low platelets (thrombocytopaenia)

Answer 12

penicillamine (treatment for RA) - reduces production of platelets
Heparin - incr destruction of platelets

Question 13

CPY450 inducers (7main types)

Answer 13

antiepileptics: phenytoin, carbamazepine
barbiturates: phenobarbitone
rifampicin
St John’s Wort
chronic alcohol intake
griseofulvin
smoking (affects CYP1A2, reason why smokers require more aminophylline)

Question 14

CPY50 inhibitors (11 main types)

Answer 14

antibiotics: ciprofloxacin, clarithromycine/erythromycin
isoniazid
cimetidine,omeprazole
amiodarone
allopurinol
imidazoles: ketoconazole, fluconazole
SSRIs: fluoxetine, sertraline
ritonavir
sodium valproate
acute alcohol intake
quinupristin

Question 15

adverse effect of azathioprine

Answer 15

bone marrow depression
pandreatitis
incr risk of non-melanoma skni cancer

Question 16

Drugs causing myelosuppression/agranolocytosis

Answer 16

• methotrexate
• azathioprine
• carbimazole
• pheytoin
• carbamazepine

Question 17

TCA adverse effects caused by
1. antagonism of histamine receptors
2. antagonism of muscarinic receptors
3. antagonism of adrenergic receptors
4. other important AE

Answer 17

1. drowsiness
2. dry mouth; blurred vision; constipation; urinary retention
3. postural hypotension
4. lengthening QT interval

Question 18

Drugs causing urinary retention (5)

Answer 18

• TCAs
• anticholinergics= antipsychotics, antihistamines
• opioids
• NSAIDs
• disopyramide

Question 19

Psychiatric drugs which reduce seizure threshold (2)

Answer 19

• ciprofloxacin
• antipsychotics

Question 20

Quinolone antibiotics
1. examples
2. AE (4)

Answer 20

1. ciprofloxacin, levofloxacin
2. • Lower seizure threshold (in epilepsy)
   • Tendon damage (incl rupture) - > if also on steroids
   • cartilage damage (in animal models) - avoid in children
   • lengthens QT interval

Question 21

Lithium adverse effects (9)

Answer 21

• N&V, D
• fine tremor
• nephrotoxicity (polyuria 2ry to nephrogenic diabetes insipidus)
• thyoid enlargement –> +/- hypothyroidism
• ECG = T wave flattening/inversion
• weight gain
• idiopathic intracranial hypertension
• leucocytosis
• hyperparathyroidism + hypercalcaemia

Question 22

Extrapyramidal side effects

Answer 22

• parkinsonism
• acute dystonia (sustained mucle contraction – torticollis, oculogyric crisis)
• akathisia (severe restlessness)
• tardive dyskinesia (late onset of choreoathetoid movement - abnormal involuntary movements)

Question 23

Main adverse effects of typical antipsychotics
+ examples of drugs

Answer 23

main:
- extrapyramidal side-effects
- hyperprolactinaemia common

other:
- prolonged QT (haloperidol)
- neuroleptic malignant syndrome
- impaired glucose tolerance
- antimuscarinic (dry mouth, blurred vision, urinary retention, constipation)

haloperidol, chlorpromazine

Question 24

Atypical antipsychotics main AE

Answer 24

metabolic effects
extrapyramidal side-effects and yperprolactinaemia are less common

greater reduced seizure threshold

Question 25

Drug causing impaired glucose tolerance

Answer 25

thiazides, furosemide (less common)
steroids
tacrolimus, ciclosporin
interferon-alpha
nicotinic acid
antipsychotics

Question 26

Fts of heparin-induced thrombocytopenia (HIT)

Answer 26

• immune mediated = antibodies against complex of platelet factor and heparin –> induce platelet activation
• is actually pro-thrombotic
• clinically = 50% reductin in platelts + thrombosis + skin allergy
• 5-10 days of tx with heparin (IV heparin, usually used in renal failure/high risk bleeding needing anticoag that is short acting) - low risk with LMWH

Question 27

AE of heparins

Answer 27

• bleeding
• hyperkalaemia (?inhibition of aldosterone secretion)

mainly standard/unfractionated heparin:
- thrombocytopenia (HIT)
- osteoporosis/incr risk of fractures

Question 28

TB drugs + AE/SE (4)

Answer 28

• rifampicin: hepatitis, orange secretions, flu-like
• isoniazide: hepatitis, agranulocytosis, peripheral neuropathy (add vit B6)
• pyrazinamide: hyperuricaemia->gout, hepatitis, arthralgia/myalgia
• ethanbutol: optic neuritis (baseline visual acuity), decr dose in renal impairment