Antiepileptic drugs are the essential treatment option for almost all epilepsy. Their mode of action is prophylactic. Taking antiepileptic drugs is intended to prevent epileptic seizures from occurring. The causes of the illnesses remain unaffected. These cannot be addressed by medication. Nevertheless, epilepsy can heal over the course of a longer seizure-free period and the medication can then be discontinued. However, two thirds of all epilepsy patients are subject to lifelong pharmacological therapy. In addition to prophylactic use in the case of epilepsy, antiepileptic drugs are also used for other diseases, e.g. B. in neuropathic pain.

Epilepsy is one of the most common neurological diseases in Germany. It affects around 0.6 to 0.8 percent of the population, which is 500,000 to 650,000 people in Germany (cf. Päfflin 2011). According to the WHO, around 50 million people worldwide suffer from epilepsy.
The word epilepsy, which comes from the Greek, means something like: “to be seized” or “to be affected by something”. Epilepsies are a group of different diseases. What they have in common is that epileptic seizures occur from time to time - and usually for no apparent reason.
An epileptic seizure is due to a temporary disruption of the electro-chemical balance in the brain. During an epileptic seizure, the electrical and chemical balance of billions of neurons in the brain is disrupted. This happens through sudden discharge in individual brain regions. When it comes to epileptic seizures, a distinction is made between focal and generalized seizures: Focal seizures arise from a focus of the disease. In them, only one brain region in one half of the brain is affected. In generalized seizures, however, the entire brain is affected. Furthermore, various types of seizures can be differentiated (cf. Brandt 2009).
Epileptic seizures and epilepsy do not occur with the same frequency at every age. Although this fact of age-dependent occurrence has been known for a long time, little is known about the causes of age-related occurrence. There are various hypotheses about this. Another characteristic of the disease is that the types of seizures can change over the course of life. (see Borusiak 2008).
Antiepileptic drugs - different modes of action
Antiepileptic drugs or anticonvulsants (ATC-EphMRA: N03) are the first choice treatment option for epilepsy. This is a chemically heterogeneous group. With regard to the mode of action, a distinction can be made as to whether the aim is to block epileptic impulses or to prevent the spread of epileptic impulses. There are more than 20 different medications available for pharmacological therapy, which are divided into three groups. The first group includes the commonly used anticonvulsants such as pregabalin, gabapentin or carbamazepine. Group 2 contains active ingredients that are more suitable for acute therapy, e.g. B. Benzodiazepines such as lorazepam. The third group includes anticonvulsants such as sultiam, primidone or rufinamide, which are used rarely and in specific indications or as add-on therapy (see AWMF guideline “First epileptic seizure and epilepsy in adults”, 2008).
The therapy is selected taking into account the type of epilepsy and the presenting syndrome, the side effect profile and risk potential, the costs and the doctor's diagnostic assessment. On the one hand, a decision must be made as to what type of epileptic seizure is present, and on the other hand, tolerability, safety, price and specific patient needs play an important role (cf. Rating 2008).

350 million DDD anti-epileptic drugs
According to the current sliding annual value MAT 09/2012, a good 350 million daily therapy doses (DDD) of antiepileptic drugs were prescribed within the GKV. In 2011 it was 3 percent less. Overall, there has been a continuous increase in consumption - measured in prescribed DDD (see Fig. 1). The basis for this analysis is the regioMA care database from INSIGHT Health. This includes, among other things, a comprehensive DDD classification and links this with a quasi-complete survey of outpatient GKV prescription information. INSIGHT Health determines the factors for determining the daily therapy doses for each PZN on a monthly basis based on the DDD definition (WHO/WIdO) in coordination with the IGES Institute.
Figure 2 gives an overview of the essential antiepileptic drugs measured in defined daily therapy doses. It can be seen that the three most prescribed active ingredients pregabalin (18%), carbamazepine (15%) and levetiracetam (13%) together account for almost half of all prescribed daily therapy doses.
On the side of prescriptions and sales (valued at list prices), an opposite development can currently be seen: While around 9.5 million packs with an output volume of 869 million euros (valued at pharmacy sales prices) were sold in 2011, there is currently an increase in the quantity with simultaneously falling sales (MAT 09/2012: 9.7 million packs at 848 million euros).
This is primarily due to the expiring patent protection of levetiracetam. This active ingredient, known under the trade name Keppra, currently accounts for more than a seventh of all prescribed daily therapy doses of anticonvulsants.
It is important to note that not every patient treated with antiepileptic drugs suffers from epilepsy. The reason for this is that antiepileptic drugs are not only used in epilepsy, but
e.g. B. also in the comparatively common neuropathic pain (see DARWIN, INSIGHT Health). The active ingredients gabapentin and pregabalin, for example, are used in addition to the treatment of epilepsy for the symptomatic treatment of neuropathic pain or neuralgia (see Medicines Atlas 2012, p. 293).

Partial indication: neuropathic pain

Chronic neuropathic pain is a common condition. The prevalence of this disease is up to 5 percent of the total population. Examples of neuropathic pain include painful diabetic polyneuropathy and postherpetic neuralgia. This pain occurs after damage to somatosensory nerve structures in the central or peripheral nervous system. They manifest themselves, among other things, in a so-called allodynia, a mechanical hypersensitivity. The diagnosis of neuropathic pain is based on objective evidence of a lesion in the nervous system and typical somatosensory symptoms.
The general therapy principles are based on the individual adjustment of the medication to the individual patient. Long-term therapy monitoring is essential because the effects of the individual substances and the development of tolerance must be recorded. In addition to the frequently used anticonvulsants, pregabalin, gaba-
pentine or carbamazepine, antidepressants, classic pain medications such as tramadol, topical therapies such as lidocaine and cannabinoids are also available (see Dtsch. Ärzteblatt 2006; 103(41): A 2720-30).

Treatment prevalence: 2 million people insured by statutory health insurance

According to a recent study by INSIGHT Health, there was a shortage in Germany in 2011. 2 million GKV patients treated with antiepileptic drugs (ATC EphMRA: N03). This corresponds to 2.9 percent of those insured by statutory health insurance.
Older people in particular are increasingly prescribed antiepileptic drugs around the age of 70. The prevalence of treatment increases noticeably from the age of 40 years. The average age is 61 years. The proportion of women is 57 percent. 3.1 percent of women with statutory health insurance received anticonvulsants in 2011 and 2.6 percent of men with statutory health insurance.
This information comes from INSIGHT Health's Navi4Data analysis tool. Patient numbers from an anonymized representative panel of GKV insured persons of up to 65 percent of GKV prescriptions (source: Patient Tracking, INSIGHT Health) were extrapolated for the year 2011 using a quasi-complete survey of billed GKV prescriptions (source: NVI, INSIGHT Health).
Current discussion on exchange bans
In the current debate, antiepileptic drugs are being discussed in the context of discount agreements according to Section 130a(8) SGB V and also the decided possibility of exchange bans. It is undisputed that generics contribute significantly to the realization of potential savings within the statutory health insurance system. However, before changing (generic) medication due to aspects of bioavailability and the associated risk of relapse, especially in seizure-free patients, careful risk assessments and appropriate patient information should be carried out. In contrast, the new and permanent adjustment to a specific generic drug is medically unproblematic.
In this context, it will also be interesting to see whether the Federal Joint Committee (G-BA) calls for an early benefit assessment of the active ingredient pregabalin - one of the highest-selling active ingredients from the existing market, which still enjoys documentation protection. It is also conceivable that lower-selling active ingredients will initially be called up for other indications where a change in therapy tends to be associated with fewer complications. <<

from:
Christian Bensing /
Dr. Andre Kleinfeld