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A syncope is defined as a sudden, temporary loss of consciousness, associated with loss of postural tone with spontaneous recovery. The incidence is high and the differential diagnosis broad; therefore, the first observations are essential for the management of the patient. In this review diseases will be described which manifest themselves with syncopes that fall under the auspices of either internal medicine or neurology. First, the etiologies of syncopes are discussed in the strict sense of the word, i.e. due to a global cerebral ischemia such as in orthostatic hypotension and vasopressor syncopes. Thereafter, a discussion concerning the differential diagnosis of syncopes will be introduced, including mainly psychogenic and epileptic seizures as well as vertebrobasilar hypoperfusion. Depending on the reason of the loss of consciousness, it can be a common benign disorder or a severe life-threatening disease. The personal history or witness account of the incidence provides the most useful information concerning diagnosis. The cardiological diagnostic procedures are discussed elsewhere. In some instances an EEG can further help with the diagnosis. In many cases an etiology can't be found, even if extensive investigations have been performed.

New antiepileptic drugs such as vigabatrin, lamotrigine, gabapentin, oxcarbazepine and felbamate have been lately marketed. This article provides an overview, showing known modes of action, pharmacokinetics, efficacy, tolerability, interactions and indications. A table showing selected data of antiepileptic drugs is included.

In Switzerland valproate is in use as an anticonvulsant drug since 25 years. On this occasion we present a synopsis of the state of knowledge about its mechanism of action, pharmacokinetics, clinical efficacy, side effects, drug interactions, and administration with respect to special clinical situations.

Single fits and epileptic illness are more frequent in advanced age; their occurrence reaches the same frequency as in the neonatal period. Their origin and the possibilities of treatment are tightly connected to the process of ageing, a fact that requires special consideration. The main reasons for new epileptic attacks in the group of age 65 or more are structural changes, i.e. ischemic infarctions, tumors and atrophic involution. For certain patients, the use of antiepileptic drugs may be limited by unavoidable side effects. Complete cure of the attacks in advanced age is rare, but with a well selected treatment sufficient control is often possible.

We present the concept of an 'epileptic syndrome' which is important for prognostic statements and the application of appropriate therapeutic measures. We then discuss the epileptic seizure and the assessment of suspected seizure, indications for admission to a hospital, diagnostic measures (EEG, CT scan, laboratory tests, lumbal puncture, MRI scan, PET scan, angiography), therapy and procedures for imminent status epilepticus. Finally, we try to answer the question whether anticonvulsant medication should be instituted after a first epileptic seizure.

Repeated administration of diazepam in two ventilated patients had caused drug cumulation and coma over several days. In both cases central nervous depression could be demonstrated by the benzodiazepin antagonist Ro 15-1788 which induced reversal of coma. Estimation of plasma concentrations in a 70-year-old female patient 150 hours after the last administration showed a diazepam concentration of 437 ng/ml and a desmethyl-diazepam concentration of 483 ng/ml. The calculated elimination half-life of these substances were 109 and 403 hours. In the second case benzodiazepin could be demonstrated in urine for 10 days after withdrawal of medication. These observations suggest that diazepam is not a suitable drug for prolonged sedation in artificially ventilated patients. The benzodiazepin antagonist Ro 15-1788 represents a valuable diagnostic aid in ascertained or suspect cases of benzodiazepin intoxications. It can also be used therapeutically for reversal of central nervous depression.

In this overview the current state of knowledge concerning epilepsy is presented: diagnosis, classification, etiology, pathogenesis and therapy. The change in these aspects during the past epochs of medical history is described. Suggestions as to future prospects are discussed.

A 24-year-old female with gastrointestinal disturbances, nausea and vomiting, had a convulsion with loss of urine and bitten lips on the 5th day of hospitalization. A significant decrease of sodium and potassium levels and lowered osmolality of the serum as well as urinary hyperosmolality permitted the diagnosis of the so-called syndrome of inappropriate antidiuretic hormone release (SIADH) of unknown aetiology, described by Schwartz-Bartter. Twice short tests for porphyria were negative; then the elevated porphyrin precursors collected in 24 h urine indicated the existence of an acute intermittent porphyria. A clinical follow-up and improvement were demonstrated by the EEG findings. Since animal experiments and pathohistological findings indicate that porphyrin metabolites such as delta-amino laevulinic acid and porphobilinogen may influence inhibitory and neurosecretory structures in central nervous tissue and interfere with GABA, cerebral hyperexcitability as well as disturbance of electrolytes may be explained. Finally, the question of whether the EEG changes are due to the significant electrolyte disturbances or are typical signs of acute intermittent porphyria is discussed.

After mentioning the therapeutic effect of anti-convulsant medication on the pathophysiology of epileptic seizures the principal anticonvulsive drugs are characterized in a table. Furthermore their interactions with non-anticonvulsive drugs are pointed out, as well as side-effects. Some statements are made concerning genetic and psychosocial considerations.

193 patients with epilepsy were investigated by EEG and by computerized tomography (C.T.). 55.5% of the pathological C.T. scans were found in partial seizures with elementary symptomatology. In patients with generalized seizures the diagnosis of symptomatic epilepsy could be made in 40 cases (35.7%) with the help of computerized tomography. In 38 EEG there was a continual delta-wave focus, 18 of these with epileptogenic activity. Of these 38 patients, 34 showed a pathological result in computerized tomography. 19 tumors or metastases, 11 cases of atrophy (10 local and one diffuse) as well as one case of encephalitis could be diagnosed. The remaining 3 patients showed indefinate findings with C.T. 19 EEG showed intermittent theta-wave foci. Computerized tomography gave 5 pathological scans in these patients. If one compares the results of computerized tomography and EEG in cases of tumor, the agreement between positive tomography and the pathological EEG is very high (95%): 64 positive C.T. compared with 61 positive EEG. Our investigations with computerized tomography show organic findings in 67 of 193 epilepsies, that is about 35%.