A Double-blind, Randomised, Placebo-controlled, Rising Multiple Dose Study to Investigate the Safety, Tolerability, Steady State Pharmacokinetic Profile and CNS Effects of BIA 2-093

* Inclusion Criteria: * Adult males aged 18-45 years, with a body mass index (BMI) of 19-28 kg/m2. * Subjects who were healthy as determined by pre-study medical history, physical examination, 12-lead ECG and EEG. * Subjects who had clinical laboratory tests acceptable to the investigator. * Subjects who were negative for HbsAg, anti-HCV and HIV I and II tests at screening. * Subjects who were negative for drugs of abuse and alcohol tests at screening and admission. * Subjects who were non-smokers or previous smokers who had not smoked for at least 6 months. * Subjects who were able and willing to give written informed consent. * Exclusion Criteria: * Subjects who did not conform to the above inclusion criteria. * Subjects who had a clinically relevant history or presence of respiratory, gastrointestinal, renal, hepatic, haematological, lymphatic, neurological, cardiovascular, psychiatric, musculoskeletal, genitourinary, immunological, dermatological, connective tissue diseases or disorders. * Subjects who had a clinically relevant surgical history. * Subjects who had a clinically relevant family history. * Subjects who had a history of relevant atopy. * Subjects who had a history of relevant drug hypersensitivity (carbamazepine and * related compounds). * Subjects who had a history of alcoholism. * Subjects who had a history of drug abuse. * Subjects who consumed more than 28 units of alcohol a week. * Subjects who had a significant infection or known inflammatory process on screening and/or admission. * Subjects who had acute gastrointestinal symptoms at the time of screening and/or admission (e.g. nausea, vomiting, diarrhoea, heartburn). * Subjects who had an acute infection such as influenza at the time of screening and/or admission. * Subjects who had used prescription drugs within 4 weeks of first dosing. * Subjects who had used over the counter medication, excluding routine vitamins but including mega dose vitamin therapy, within one week of dosing. * Subjects who had used any investigational drug and/or participated in any clinical trial within 3 months of admission to this study. * Subjects who had donated and/or received any blood or blood products within 3 months prior to screening. * Subjects who were vegetarians, vegans and/or had medical dietary restrictions. * Subjects who could not communicate reliably with the investigator. * Subjects who were unlikely to co-operate with the requirements of the study. * Subjects who were unwilling or unable to give written informed consent. * Subjects who had previously received BIA 2-093.