Antiepileptic drugs in epilepsy and other disorders--a population-based study of prescriptions.
OBJECTIVE
The aim of the study was to quantify the use of antiepileptic drugs (AEDs) in epilepsy and other indications in a nation-wide population using a prescription database.


METHODS
Prescription data of AEDs were collected from the Norwegian Prescription Database for the period 2004-2007, including 5.1 million prescriptions from 144,653 patients, all having at least one prescribed and dispensed AED. Diagnosis-related reimbursement codes were used as indicators for clinical use.


RESULTS
Of the AEDs used, 71% was in epilepsy, 15% in psychiatry, 13% in neuropathic pain, and <1% in migraine, trigeminus neuralgia and cancer adjuvance. The use in epilepsy increased steadily from 7.0 to 7.5 DDDs/1000 inhabitants/day (7%) from 2004 to 2007. The use of AEDs in other indications increased considerably more from 2004 to 2007: Neuropathic pain to 1.40 DDDs/1000 inhabitants/day (360%), psychiatry to 1.59 (200%), and migraine to 0.005 (642%). The prevalence of AED users increased and in 2007 it was 0.97% in epilepsy, 0.8% in neuropathic pain, 0.33% in psychiatry and 0.001% in migraine. In 2007, 49% of the AEDs used in epilepsy were a new drug, carbamazepine, lamotrigine and valproate being most frequently used. New AEDs were used in 96% in migraine prophylaxis, 94% in neuropathic pain, and 64% in psychiatry.


CONCLUSIONS
Based on a nation-wide prescription database, this study quantifies the wide and increasing use of AEDs, in particular the newer drugs.
Johannessen Landmark
Cecilie
C
Department of Pharmacy, Faculty of Health Sciences, Oslo University College, Pilestredet 50, N-0167 Oslo, Norway. cecilie.landmark@hf.hio.no
Larsson
Pål G
PG
Rytter
Elisif
E
Johannessen
Svein I
SI
D000927:Anticonvulsants / Q000627:therapeutic use*; D016208:Databases, Factual; D011307:Drug Prescriptions; D004363:Drug Utilization; D004827:Epilepsy / Q000188:drug therapy*; D019983:Guideline Adherence; D006801:Humans; D008881:Migraine Disorders / Q000188:drug therapy; D010818:Practice Patterns, Physicians'; D014277:Trigeminal Neuralgia / Q000188:drug therapy
D000927:Anticonvulsants