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. Con’t ( 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 > 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 > 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 patient’s 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 patient’s choice • Ethical/practical choice behind patient • Informed choice • Ironically, complying with patient’s 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 patient’s 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 patient’s 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 • > Errors in manufacturing, supplying, prescribling, giving or taking medicine • Intrinsic • > 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 > 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 OPD:just under 3 • UK:just 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 > 3 or more drugs • < 50% finished all the medication

31. 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 fallibility:inadequate 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 >more training to communicate with patients about risk and benefit >training in decision analysis >undergraduate/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