Volume and market share of anti-epileptic drugs in The Netherlands: impact of new drugs.

Item does not contain fulltextOBJECTIVE: In the past decade, several new anti-epileptic drugs (AEDs) were introduced in The Netherlands. These new drugs, one of which is lamotrigine, are 6 to 10 times more expensive than conventional anti-convulsants. In 1997, the high cost of lamotrigine, together with a lack of clinical data supporting its superiority over conventional drugs, prompted the Dutch Health Insurance Board to release a guideline in which the use of lamotrigine was restricted to difficult-to-treat patients. Other new drugs that were marketed after 1997 also became subject to this guideline. The utilisation of new AEDs and the cost consequences are the subject of this paper. METHODS: Data from extramurally prescribed AEDs was obtained from the Dutch Drug Information Project, which is a database containing prescriptions for about 5.5 million inhabitants of the Netherlands. This data was used to study the impact of new AEDs on volume and market share of AEDs in the period from 1995 to 2001 in The Netherlands. RESULTS: Between 1995 and 2001, the total volume of AEDs increased by 130%, 60% of which consisted of new AEDs. Gabapentin, lamotrigine and oxcarbazepine were the most frequently prescribed new compounds. The volume share of new AEDs increased from 5% in 1995 to 18% in 2001. The market share amounted to 21.5 million euros in 1995 and rose to 47 million euros in 2001; 80% of this increase was due to the introduction of new AEDs. DISCUSSION: Although in 2001 the volume share of new AEDs was still modest, their introduction has led to a strong increase in the cost. New data is emerging on the effectiveness and cost-benefit sum of the new AEDs; this may change the place in therapy of these drugs. Because of their strong potential to force up cost, the positioning of new AEDs requires further attention

Snails have stronger indirect positive effects on submerged macrophyte growth attributes than zooplankton

Phytoplankton and epiphyton often compete with submerged macrophytes. Grazing by zooplankton and/or epiphyton grazers should promote an indirect positive effect on submerged macrophyte growth rate. Hence, we mimicked shallow lakes conditions in mesocosms using a factorial design to evaluate the indirect effects of no grazers, zooplankton, snails or both grazers on macrophyte growth attributes. After 16 weeks, both snails and zooplankton had positive effects on macrophyte stem length and biomass. However, only snails had positive effects on macrophyte number of sprouts and root biomass. In addition, the positive effect size of snails on the submerged macrophytes was twice as large as the effect size of the zooplankton. Our study suggests that benthic food chains might be more capable of increasing resilience and affecting the stability of the clear-water state in shallow lakes than pelagic food chains. However, long-term experiments with varying relative proportions of herbivores and different macrophyte species, as well as in situ experiments, will be necessary to test the generality of our findings. Understanding the relative effects of benthic versus pelagic grazers on submerged macrophytes may increase the success of shallow lake restoration and should be taken into account when designing management and restoration efforts for shallow lake systems

The management of bipolar disorder in primary care : a review of existing and emerging therapies

Recent evidence suggests that the prevalence of bipolar disorder is as much as fivefold higher than previously believed, and may amount to nearly 5% of the population, making it almost as common as unipolar major depression. It is, therefore, not unrealistic to assume that primary care or family physicians will frequently encounter bipolar patients in their practice. Such patients may present with a depressive episode, for a variety of medical reasons, for longer-term maintenance after stabilization, and even with an acute manic episode. Whatever the reason, a working knowledge of current trends in the acute and longer-term management of bipolar disorder would be helpful to the primary care physician. In addition, an understanding of important side-effects and drug interactions that occur with drugs used to treat bipolar disorder, which may be encountered in the medical setting, are paramount. This paper will attempt to review existing and emerging therapies in bipolar disorder, as well as their common drug interactions and side-effects.<br /