Adverse drug reactions Flashcards
1st gen antihistamines such as promethazine can give u
sedation
tergenadine (antihistamine) can give u
arrhythmias (drug acts on histamines receptors but also act on cardiac K+ channels as well)
drugs with narrow therapeutic window
digoxin
warfarin
aminoglycosides
drugs with steep dose-response curve
sulphonylureas
verapamil
levodopa
hypersensitivity reactions if immediate are
IgE mediated aka drug allergy
or if delayed, its non-IgE mediated
in the initial exposure theres no ADR, but it sensitises the body. its with SUBSEQUENT exposure that u get ADRs
type 2 hypersensitivity reaction example
haemolytic anaemia from penicillin
type 3 hypersensitivity reaction example
serum sickness from anti-thymocyteglobulin
type 1 hypersensitivity reaction example
anaphylaxisfrom penicillin
IgE-mediated
pseudoallergy example
red-man syndrome with vancomycin
corticosteroids can give u
cushings
alkylating agents can give u
secondary cnacers
diuretics and digoxin
diuretics gets rids of K+
Digoxin inhibits the Na+/K+ ATPase
if u have less K+, then that channel won’t work very well,
=get digoxin toxicity e.g. dysrhythmia
sildenofil (viagra) and nitrates
sildenafil blocks the thing (PDE-5) that breaks down cGMP
nitrates stimulate cGMP to do vasodilation
so if u have more cGMP, nitrates can work more
=get hypotension
st johns wort and SSRIs
st johns wort inhibits 5HT uptake
SSRIs also inhibit 5HT uptake
=can get serotonin toxicity
drugs that induce cytochrome P450 (cytochrome P450 breaks down drugs)
rifampicin
st johns wort
drugs that block cytochrome P450 (cyto P450 breaks down drugs)
grapefruit juice
st johns wort
have both pharmacokinetic interaction and pharmacodynamic interaction
induces CYP3A4 in liver
same effect as SSRIs, so if given together get serotonin syndrome
2 drugs that increase urine flow
diuretic s and digoxin
2 drugs that compete for the same transporter during renal drug excretion
penicillin & probenecid
