A system and method for detecting and analysing the characteristics of seizures, such as tonic-clonic seizures, comprising at least one processor unit (3) capable of recording a signal (5) from a sensor unit (3), one or more analysis modules (6, 8) configured to analyse the recorded signal (5), one or more evaluation modules (10) configured to evaluate the output signals (9) from the analysis modules (6, 8). A first analysis module (8a) is configured to analyse the recorded signal (7a) within a first frequency band (BHF), and a second analysis module (8b) is configured to analyse the recorded signal (7b) within a second frequency band (BLF), and the evaluation module (10) is configured to calculate the ratio (HF/LF) between the two output signals (9a, 9b) from the analysis modules (8a, 8b). The system comprises a seizure detection module (21) configured to detect a seizure and a time-point extraction module (11) configured to determine at least one starting point (T0, T2) and an end point (T3) of the seizure.
