ADRs are categorized into two types:
predictable (type A) and unpredictable (type B)
Type A reactions are
dose-dependent, related to the known pharmacologic properties of the drug can occur in any patient and range from mild to severe
(most common reaction)
Examples of type A reactions
orthostatic hypotension with doxazosin
nephrotoxicity with aminoglycosides
Type B reactions are
not dose-dependent, are unrelated to the pharmacologic actions of the drug and can be influenced by patient-specific factors (genetics)
Type B reactions are categorized as
immediate (occurring within 60 mins after exposure) and delayed (occurring days to months after exposure)
Define type I reactions- immediate
IgE- mediated, ranging from minor local reactions to severe systemic reactions
(ex: urticaria, angioedema, anaphylaxis)
Define type II reactions- delayed
antibody-mediated, usually occurring 5-8 days after exposure
(ex: hemolytic anemia, thrombocytopenia)
Define type III reactions- delayed
immune-complex reactions, occurring ≥ 1 week after exposure
(ex: serum sickness)
Define type IV reactions- delayed
T- cell mediated, occurring 48 hours to weeks after exposure
(ex: SJS)
Define thrombotic thrombocytopenic purpura
blood disorder in which clots form throughout the body, the clotting process consumes platelets and leads to bleeding under the kin and the formation purpura (bruises) and petechiae (dots) on the skin
SJS and TENS involve
epidermal detachment and skin loss that is equivalent to third degree burn (generally occur 1-3 weeks after drug exposure)
Systemic steroids are contraindicated with
TEN but may be used for SJS
Anaphylaxis treatment includes
epinephrine injection + diphenhydramine +/- steroids +/- IV fluids
Adult dose for epinephrine
0.3 mg
Pediatric dose for epinephrine
0.15 mg
beta-lactams should be avoided with a
stated allergy to another beta-lactam
What monobactam is considered safe in patients with an immediate-type penicillin allergy
aztreonam
Side effects, adverse events and allergies should be reported to the
FDAs MedWatch program which is called the FDA Adverse Event Reporting System (FAERS)
The FDA can required ______ for approved drugs and biologics, to collect and analyze ADR reports and better understand a drug's safety profile
phase IV trials
A boxed warning indicates
a risk of death or permanent disability
Contraindications indicate that
the drug cannot be used in patient
(the risk will outweigh possible benefit)