3. 3
TYPE A (Augmented) TYPE B (Bizarre)
Dose – related Non dose – related
Predictable Unpredictable
Common Uncommon
Normally reversible Maybe serious / irreversible
Manageable with dosage adjustment Drug discontinuation needed
Eg. Warfarin - Bleeding Eg. Beta blockers - Bronchospasm
Traditional Classification
4. - Rowlins and Thompson
4
Type Name Example
Type C Chronic Corticosteroid – adrenal suppression
Type D Delayed Neuroleptics – Tardive dyskinesia
Type E End of use Opiates – Withdrawal syndrome
Type F Failure of therapy Decreased effect due to antibiotic resistance
6. DoTS Classification
6
Dose
Toxic
ADRs that are
generally
observed with
drug levels that
are too high
Collateral
ADRs that can
happen in usual
therapeutic
range
Hyper
susceptibility
ADRs that can
even occur in
low,
subtherapeutic
doses
7. 7
DoTS Classification
Time
Dependant
Independent:
NSAIDs –
Renal Failure
Early: nitrate
induced headache
Intermediate: Type
II, III, IV
hypersensitivity
Late: Antipsychotics
– tardive dyskinesia
Delayed:
Cancer
Withdrawal:
Opiates –
withdrawal
syndrome
First dose:
Penicillin
anaphylaxis
Rapid
administration:
Vancomycin –
red man
syndrome
8. 8
DoTS Classification
Susceptibility
Gender:
-Females are
more prone to
ADRs
Age:
- Elderly and
pediatrics
-Elderly patients
are more
sensitive to
antipsychotics
and anxiolytics
Ethnic origin:
G6PD deficiency
High risk of
hemolysis with
nitrofurantoin or
quinolone
antibtiotics
Genetics:
CYP2C9
polymorphisms -
bleeding
Disease:
Hepatic or renal
disease – kinetics
is altered
9. Examples:
1. Corticosteroids – Osteoporosis
Dose – Collateral
Time - Late
Susceptibility – Age & sex
2. Anaphylaxis of penicillin
Dose: hypersensitivity
Time – First dose
Susceptibility – requires previous sensitization
9
10. DoTS Classification
10
Gaining acceptance
ADRs do not clearly fit in the traditional classification
Provides pointers on how specific ARDs can be avoided