adverse reactions of drugs

Question 1

adr

Answer 1

ANY undesirable reaction that detriments wellbeing of patient

Question 2

adrs most commonly in

Answer 2

elderly n frail
multimorbid (renal/hepatic clearance etc)
polypharmacy

Question 3

some drugs w/ narrow therapeutic index

Answer 3

theophylinne, warfarin, lithium, digoxin, gentamicin

Question 4

phases of drug metabolism

Answer 4

phase 1 - usually through Cyp P450 , oxidation, reduction and hydrolysis

phase 2 - conjugation (water soluble) , enables excretion in urine/bile

ADRs almost always due to phase I interactions

Question 5

classification types

Answer 5

a - augmented
b - bizarre
c - chronic
d - delayed
e - end of treatment
f - failure of therapy

Question 6

type a dose dependent and predictable

Answer 6

1) pre renal - hypotension, hypovolemia e.g. diurectics hf dehydration , acei/arbs - d&v

2) renal - AIN/tubular necrosis ATN e.g. gentamicin - sepsis, sulphonamides - RA, aspirin - CV disease (gent toxicity)

3) post renal - retroperitoneal fibrosis, crystaluria, urinary calculi e.g methysergide - cluster headaches , chemotherapy - acute leukaemias

4) drug interactions - later

Question 7

drug - drug interactions examples

Answer 7

theophylline macrolide antibiotics, statins and macrolides / statins and fibrates, TCAs and type 1 anti-arrythmics , warfrarin and multiple drugs, ACEis increase hypoclycaemic effect of sulfonylureas, clopidogrel and PPIs

Question 8

eggyzamps of drug herb reactions

Answer 8

vitamin c grapefruit (cyp p450)
dementia gingko biloba (anticoag)
BPH saw palmetto (anticoag)
OA glucosamine (hyperglyc , anticoag)
depression st johns wort (CoC)

Question 9

drug disease interact eggys

Answer 9

parkinsons - drug induced confusion, nsaids cox2 tzds can exacerbate CHF

urinary retention in BPH patients on decongestants or anticholinergics

constipation worsened by calcium, anticholinergics, ccbs

neuroleptics, tramadol and quinolones lower seizure threshold

beta blockers and asthma

Question 10

drugs n scran!!

Answer 10

bananas, orange, leefy gweens veggies (K rich) interact w/ ACEIs, ARBs, K-sparing diuretics

apples, chickpeas, spinach, nutsm kiwi, broccoli (vitmain E & K) w/ warfarin

chicken, turkey, milk, soy, cheese, yoghurt (alter pH) interacting w/ ABs, thyroid meds, digoxins, diuretics

grapefruit, apple, orange cranberry (cytochrome P450) interacts w/ /statins, antihistamines

Question 11

type B dose independent and unpredictable egs

Answer 11

drug rashes
bone marrow aplasia - chloramphenicol antibiotic
hepatic necrosis - halothane
HIGH MORTALITY

Question 12

type c (chronic)

Answer 12

prolonged e.g. steroid therapy cushings, betablockers diabetes, nsaids hypertension, type c reactions emphasise drug therapy monitoring, can be anticipated but patient must be warned before starting therapy

Question 13

type d delayed

Answer 13

remote from treatment, many years after stopping, teratogenic/carcinogenic, devastating, less frequent now due to rigorous pre-clinical e.g. secondary malignancies post chemo, craniofacial in babies whos mum isotret

Question 14

type e end of treatment

Answer 14

abrupt withdrawal, rebound effects
e.g. betablocker withdrawal and angina loss of phsyiological coping

steroid withdrawal n addisonian crisis mechanism dependent biological activity e.g. anticonvulsant withdrawal/changes and epilepsy frequency

Question 15

hla interactions

Answer 15

abacavir hypersensitivity and HLA B5701

allopurinol hypersensitivity and HLA B5801