This document discusses adverse drug reactions (ADRs), their classification and monitoring. It defines an ADR as an unintended effect of a drug that occurs at normal dosages. ADRs are classified into types A-H based on mechanisms and timing. Factors that increase risk of ADRs include polypharmacy, age, drug characteristics, and genetic predispositions. ADRs are detected through pre-marketing clinical trials, post-marketing surveillance programs, and healthcare professional reporting. Vigilant monitoring of at-risk patients can help identify ADRs.

1. ADVERSE DRUG REACTIONS (ADRs)
&
ITS MONITORING
Submitted To :
Dr. KANCHAN VOHRA
Assistant Professor
Submitted By :
Mohd. Rafi Bhat

2. Any response to a drug which is noxious and unintended,
and which occurs at doses normally used in man for
prophylaxis, diagnosis, or therapy of disease, or for the
modification of physiological function

3.  Type A(Augmented)
 Type B (Bizarre)
 Type C (Chemical)
 Type D (Delayed)
 Type E (Exit/End of treatment)
 Type F (Familial)
 Type G (Genotoxicity)
 Type H (Hypersensitivity)
 Type U (Un classified)

4. • Reactions which can be predicted from the known
pharmacology of the drug
• Dose dependent,
• Can be alleviated by a dose reduction
E.g.
• Anticoagulants  Bleeding,
• Beta blockers  Bradycardia,
• Nitrates  Headache,
• Prazosin  Postural hypotension.
TYPE A (AUGMENTED)

5. • Cannot be predicted from the pharmacology of the drug
• Not dose dependent,
• Host dependent factors important in predisposition
E.g.
• Penicillin  Anaphylaxis,
• Anticonvulsant  Hypersensitivity
TYPE B (BIZZARE) REACTIONS

6. • Biological characteristics can be predicted from the
chemical structure of the drug/metabolite
E.g.
• Paracetamol  Hepatotoxicity
TYPE C (CHEMICAL REACTIONS

7. • Occur after many years of treatment.
• Can be due to accumulation.
E.g.
• Chemotherapy  Secondary tumours
• Phenytoin during pregnancy  Teratogenic effects
• Analgesics  Nephropathy
TYPE D (DELAYED) REACTIONS

8. • Occur on withdrawal especially when drug is stopped
abruptly
E.g.
• Phenytoin withdrawal  Seizures,
• Steroid withdrawal  Adrenocortical insufficiency.
TYPE D (END OF TREATMENT ) REACTIONS

11. POLY PHARMACY :
 Patients on multiple drug therapy are more prone to
develop an ADR
 Alteration of drug effect through interaction
mechanism or by synergism
 Risk increases with increase in the no: of drugs
administered

12.  Increased risk due to multiple drugs use for their diseases
 Impaired hepatic and renal status are also at high risk of
developing an ADR
 Patient with decreased renal function treated with
aminoglycosides increased risk of nephrotoxicity

13. AGE
 Elderly and pediatric patients are more vulnerable to
ADRs
 In elderly patients physiological changes
 Eg: nitrate or ACE inhibitor induce postural
hypotension
 In neonates drug handling capacity differ compared
to adults
 Eg: grey baby syndrome with chloramphenicol

14. DRUG CHARACTERISTICS:
 Some drugs are highly toxic in nature
 Eg: cytotoxic drugs result in nausea and
vomiting
 Narrow therapeutic range drugs like digoxin
and gentamicin slight increase in concentration
may result in toxicity

15. GENDER
 Womens are more susceptible to ADRs than
males, reasons are physiological,
pharmacokinetic, pharmacodynamic and
hormonal.
 Eg: chloramphenicol induced aplastic
anaemia and phenylbutazone induced
agranulocytosis are twice and thrice as
common in women as in man,respectivley

16. RACE AND GENETIC FACTORS
 ADRs are more common in genetically predispose
individuals
 Eg : G6PD deficient patient high risk of devoleping
heamolysis due to primaquine

17. DETECTION OF ADRS
1. pre- marketing studies
2. Post –marketing surveillance
3. Under reporting
4. Communicating ADRs

18.  Identifying adverse drug reaction
(ADR).
 Assessing causality between drug and
suspected reaction by using various
algorithms.
 Documentation of ADR in patient’s medical
records.
 Reporting serious ADRs to pharmacovigilance
centers /ADR regulating authorities

19.  During the development of new medicines, their
safety is tested in animal models.
 Specific animal studies for carcinogenicity,
teratogenicity and mutagenicity are also
available.
 Clinical trials are carried out in 3 different
phases prior to the submission of a marketing
authorization application.
 Clinical trials normally identifies ADRs of
frequency greater that .5-1.0%

20.  Pharmavigilance methodologies are used for detection of
risk and for the collection of risk information
 Powerful and cost effective system for the
identification of unknown drug-related risk is
spontaneous adverse drug reactions reporting
 Health care practitioner should see it as a part of
professional duty report ADR result in a patient under
his care.
 Concerned identifying product defect, intoxicants and
abuse and unexpected lack of therapeutic effect.

21. The health care professionals should be
very vigilant in detectingADRs.
ADR may be detected during ward
rounds with medical team.
ADRs detected during review of patient
chart , patient counseling, medication
history review, communicating with other
health professionals.

22.  To assist ADR health care professionals
should closely monitor patients who are at
high risk include:
1. Patients with renal or hepatic impairment
2. Patients taking drugs which have potential to
cause ADR . Eg: DIGITOXIN
3. Patient who have had previous allergic
reactions
4. Patient taking multiple drugs
5. Pregnant and breast feeding women

23.  First step in the detection of ADRs is collection of
data.
 Data collected includes ,
1. patients demographic information
2. Presenting complaints
3. Past medication history
4. Drug therapy details including over the
counter, current medications , medication on
admission
5. Lab data such as hematological, liver and
renal function test.

24.  The information can be obtained from the following
sources:
1. Patient’s case note and treatment chart
2. Patient interview
3. Laboratory data sources
4. Communication with healthcare professionals

26. REFERENCE
Text book of clinical pharmacy practice – G
Parthasarathy . Page no: 105-118