Changing prescription patterns: impact on costs.

The cost of treating hypertension is high. In the Federal Republic of Germany the total sales of antihypertensive compounds increased, from 1981 to 1984, from 1075 million to 1525 million DM per year, corresponding to 7.4 and 9.1%, respectively, of total drug expenditure. Economists have calculated that about two-thirds of this increase is caused by structural changes within the market, i.e. changing prescription patterns. The proportion of prescribed daily doses of reserpine combinations dropped from 52 to 34% whereas that of most other compounds increased. The approximate daily costs of treatment vary from 0.5 DM (reserpine combinations) to 2.5 DM [angiotensin converting enzyme, (ACE) inhibitors], but the decline of the cheaper compounds and their substitution by newer and more expensive drugs has resulted in additional costs of 309-328 million DM. The higher prices of the new drugs should be justified by greater benefits compared with conventional compounds. Assessment of new antihypertensive drugs should include potency, efficacy, number and quality of adverse effects, and impact on quality of life. The evaluation should be performed separately for mild and for more severe forms of hypertension. Some advantages or drawbacks of the newer drugs may be important for small subgroups only.