Summary

The National Prescribing Service (NPS) has provided funds to divisions of general practice to employ facilitators. These facilitators visit general practitioners to discuss common prescribing problems. During their visits the facilitators are finding some interesting issues. Australian Prescriber is planning to publish some of these findings from time to time.

The National Prescribing Service (NPS) has provided funds to divisions of general practice to employ facilitators. These facilitators visit general practitioners to discuss common prescribing problems. During their visits the facilitators are finding some interesting issues. Australian Prescriber is planning to publish some of these findings from time to time.

Combination antihypertensives

If a patient's blood pressure cannot be controlled by lifestyle changes drug treatment is needed. Therapeutic guidelines recommend starting treatment with one drug and adjusting the dose.1 The NPS facilitators have, however, discovered that many patients are being started on fixed dose combination products.

The Drug Utilisation Sub-committee of the Pharmaceutical Benefits Advisory Committee has also found evidence that combination products are being used as first-line therapy. A review of new prescriptions for a product containing irbesartan and hydrochlorothiazide found that 17% of patients had not previously been prescribed an angiotensin receptor antagonist, an ACE inhibitor or a diuretic. Approximately 16% of patients who were prescribed a combination containing fosinopril and hydrochlorothiazide had not previously taken an ACE inhibitor, an angiotensin receptor antagonist or a diuretic.

Although some patients will need more than one drug to control their hypertension, it is best practice to start with a single product. Even some cases of severe hypertension can be managed with a single drug. Patients who do need two drugs may need doses which differ from those found in combination products. The fixed doses in these products make it difficult to titrate the dose to achieve optimum control of each patient's blood pressure.

References

  1. Writing Group for Therapeutic Guidelines: Cardiovascular. Therapeutic Guidelines: Cardiovascular. 3rd ed. Melbourne: Therapeutic Guidelines Ltd.; 1999 .