Rational prescription

1
Rational prescription

• C H Chen
• Nov., 2001

2
Mr. Wong, 65 years old, attended for follow up

• Ex-smoker, non drinker
• Come for medications 2-monthly as usual
• Good tolerance to med. Apart from on and off
  dizziness, but no history of syncope
• Problem lists HT, IHD, AF, Dizziness

3
Cont ( case 1 )

• Drug lists ( total 8 weeks of med.)
• isordil 10mg tds po
• Digoxin 0.25mg qd po
• Adalat retard 40mg bd po
• Natrilix 2.5mg om po
• Stemetil 1 tab tds po prn
• Panadol 500mg qid po prn

4
What will you do ? (case 1 )

• Continue current regime for 8 weeks more ?
• Any things do you want to know ?

5
Case 1

• BP this time gt 102/78
• Pulse 68 regular
• Physical exam revealed no sign of acute heart
  failure, but mild pitting ankle edema only
• No evidence of GIB, no pallor
• HS dual , no definite murmur heard
• Clinically not in distress

6
Case 1

• Previous BP range from 98 to 180 systolic and
  60 to 100 diastolic
• No ECG available in the old files
• Digoxin and isordil was prescribed by one of his
  private physician previously as he was told that
  he got IHD and arrthymia.
• Latest elecrolyte in Sept., 1999 gt K 3.3 with
  normal creatinine, corresponding notes reviewed
  encourage fruit intake.

7
Discussion (Case 1 )

• Blood pressure control
• Diagnosis of AF and IHD
• Dizziness

8
Good prescribing

• What do patients want and need?
• Advice
• Cure symptom relief
• Prognosis
• Certificates

9
4 aims to achieve for prescribers

• Maximize effectiveness
• Minimize risks
• Minimize costs
• Respect the patients choice

10
Maximize effectiveness

• Pharmacological manipulation of the body to
  improve or remove a condition
• Use some objective, numerical measurement to
  assess effect ( eg., BP measurement for BP
  control )

11
Minimize risks

• Reduce probability of an untoward happening
  resulting from drug treatment
• Include transient, minor side effect and adverse
  drug reaction

12
Respect the patients choice

• Ethical/practical choice behind patient
• Informed choice
• Ironically, complying with patients choice of
  treatment means poor prescriber
• Patients are more satisfied if doctors listen to
  their views, negotiating the details of drug
  treatment may improves compliance

13
conflicts

• Effectiveness and risks
• Cost effectiveness and patients choice

14
Rational prescribing

• Correct diagnosis
• Appropriate drug, dose, route and duration
• Simple regimen
• Avoid drugs if therapeutic advantage not
  supported by independent evidence
• Avoid drugs with poor risk/benefit ratios
• Review regularly and terminate if no longer
  needed

15
The most powerful drug doctor

• Understanding
• Explanation
• Reassurance and prognosis
• Placebo effect

16
Adverse drug reaction (ADR)

• Generally under-reported
• A threat to patients health and quality of care
• Generates significant expenses

17
ADR

• Unwanted or unintended effects of a medicine
  which occur during its proper use
• Extrinsic and intrinsic factors

18

• Extrinsic
• gt Errors in manufacturing, supplying,
  prescribling, giving or taking medicine
• Intrinsic
• gt inherent properties of the medicine itself may
  cause unwanted effects

19
Medication related problems

• Prescription cascade
• Misinterpretation of an adverse drug event as
  another medical condition
• Prescription of additional medications
• Non-adherence
• poor therapeutic outcomes
• higher dosages or more potent therapies

20
ADR

• Survey done at one of the university hospital in
  Switzerland
• 6 months of surveying to all primary admissions
  to medical emergency department
• Total about 7 of admissions related to ADR
• Most common being of GIB, follow by febrile
  neutropenia
• Anti-cancer drugs in 22.7 of cases

21
ADR

• Anticoagulants, analgesic and non-steroidal
  anti-inflammatory drugs in 8 of cases each

22
Case 2

• Mr. Chan, 60 years old, attended for follow up as
  usual
• Chronic smoker, social drinker
• Presented with exertional dysneoa and wheezing
• Associated with chronic dry cough
• No recent hospitalization

23
Case 2

• Claimed good drug compliance with regular usage
  of puffer
• ET gt level ground only
• Problem list COAD, HT

24
Drugs list

• Ventolin puff 2 puffs qid prn
• Atrovent puff 2 puffs qid prn
• Theodur 100mg tds po
• Bricanyl durule 7.5mg bd po
• Ventolin 4mg tds po
• Inderal 40mg tds po
• Betaloc 50mg bd po

25
Case 2

• Clinically not in distress with occ. Coughing
  only
• Chest occ. Rhonchi with poor expansion of lung
  and hence poor air entry
• BP 155/90, P 66 with occ. Ectopic heart beat
• PFR 130/150

26
Discussion (case 2 )

• Coad control
• BP control
• Side effect profiles
• Alternative choice of agents
• Treatment other than drugs

27
Are Hong Kong doctors over-prescribing?

• Expenditure on drugs per capita in HK 2-3X that
  of UK
• Items prescribed
• HK Government OPDjust under 3
• UKjust over 1

28

• Regional/international standards (national
  library of med. )
• 2 for the average of the drug
• 17 for injection
• 50 for antibiotics

29
A pill for every ill??

• Random sample of 1068 HK Chinese interviewed
  by telephone done in 1995

30
results

• 40 thought illnesses always needed drug
  treatment
• 76 expected prescription
• Almost 100 got prescription in their last
  consultation
• 85 prescription gt 3 or more drugs
• lt 50 finished all the medication

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result

• Younger age and higher education associated with
  less likelihood of expecting prescription

32
conclusion

• Chinese do not expect a pill for every ill but
  doctors prescribe in nearly 100 of consultations
• Doctors created high expectation for a
  prescription in every consultation through their
  own prescribing habit

33
The influence of patients hopes of receiving a
prescription on doctors perceptions and the
decision to prescribe a questionnaire survey

• BMJ Vol 315 6 Dec 97

34
Design

• Questionnaires to patients waiting to see GP and
  to doctors immediately after their consultations

35
Subjects

• 544 unselected patients consulting 15 GP

36
Results

• 67 patient hope for prescription
• Doctors perceived 56 patients wanted
  prescriptions
• 59 doctors prescribed
• 25 of patients hoped for a prescription did not
  receive one

37
Conclusion

• Decision to prescribe was closely related to
  actual and perceived expectations, the latter
  being more significant

38
Over-prescription of antibiotics in primary care

• 20-50 believed to be unnecessary

39
Factors responsible for inappropriate antibiotic
use

• Patient factors
• Misconception about what antibiotics do
• Misconception about healing power of antibiotics

40
Factors responsible for inappropriate antibiotic
use

• Physician factors
• Real or perceived patient pressure
• Economic concern for self e.g. loss of clients
• Physician fallibilityinadequate knowledge
• Uncertainty of the diagnosis
• Easing himself ( something done )

41
Factors responsible for inappropriate antibiotic
use

• Other factors
• Cost saving pressures to substitute therapy for
  diagnostic test
• Reduce appointment time per patient
• Misleading advertisement
• Cultural factor

42
Final comments

• Do he needs prescriptions
• Is it indicated
• Adverse drug reactions
• Risk and benefits ratio
• Polypharmacy
• Always review drug lists

43
Review drug regimen

• All new medication should started as a trial
• Substitute instead of adding on new medications
• Look for signs of adverse reactions and drug
  induced problems

44
Improving rational prescription

• Physician training
• gtmore training to communicate with patients about
  risk and benefit
• gttraining in decision analysis
• gtundergraduate/continuing education in
  therapeutics

45
Improving rational prescription

• Patient education
• Public need to be educated about the risks and
  benefits of medical interventions
• Government
• Pharmacist
• media