A system for controlling distribution of fenfluramine or a pharmaceutically acceptable salt thereof for treating symptoms of Dravet syndrome, the system comprising: a data storage facility including a database of patient records, each patient record having a medication authorization field; a central controller having one or more processors coupled to a communication network, which controls transmission and receipt of data via the network and which is coupled to the data storage facility to read and write data to the data storage facility; the central controller being programmed to output via the network an authorization of a first prescription of epilepsy medication to a specific patient dependent upon a genetic test result for that patient wherein the genetic test result relates to a test for a mutation which is selected from the group consisting of SCN1A, SCN1B, SCN2A, SCN3A, SCN9A, GABRG2, GABRD and PCDH19; and wherein the epilepsy is Dravet syndrome; and wherein the epilepsy medication is fenfluramine or a pharmaceutically acceptable salt thereof administered in a dose which is less than 0.5 mg/kg/day to 0.01 mg/kg/day; further programmed to schedule a subsequent test for the patient prior to allowing entry of a prescription for the epilepsy medication in the medication authorization field; and a portable electronic device carried or worn by the patient for monitoring patient health, the electronic device comprising a sensor for measuring information selected from the group consisting of blood pressure, electrocardiography, heart rate, blood oxygen, temperature, and lung function, wherein the electronic device is arranged to provide sensor readings in a format compatible with the central controller; and wherein an output from the electronic device is used by the central controller to determine at least one of a change to a scheduled medical test for the patient and a change to a medication prescription for the patient. a data storage facility including a database of patient records, each patient record having a medication authorization field; a central controller having one or more processors coupled to a communication network, which controls transmission and receipt of data via the network and which is coupled to the data storage facility to read and write data to the data storage facility; the central controller being programmed to output via the network an authorization of a first prescription of epilepsy medication to a specific patient dependent upon a genetic test result for that patient wherein the genetic test result relates to a test for a mutation which is selected from the group consisting of SCN1A, SCN1B, SCN2A, SCN3A, SCN9A, GABRG2, GABRD and PCDH19; and wherein the epilepsy is Dravet syndrome; and wherein the epilepsy medication is fenfluramine or a pharmaceutically acceptable salt thereof administered in a dose which is less than 0.5 mg/kg/day to 0.01 mg/kg/day; further programmed to schedule a subsequent test for the patient prior to allowing entry of a prescription for the epilepsy medication in the medication authorization field; and a portable electronic device carried or worn by the patient for monitoring patient health, the electronic device comprising a sensor for measuring information selected from the group consisting of blood pressure, electrocardiography, heart rate, blood oxygen, temperature, and lung function, wherein the electronic device is arranged to provide sensor readings in a format compatible with the central controller; and wherein an output from the electronic device is used by the central controller to determine at least one of a change to a scheduled medical test for the patient and a change to a medication prescription for the patient. wherein the electronic device is arranged to provide sensor readings in a format compatible with the central controller; and wherein an output from the electronic device is used by the central controller to determine at least one of a change to a scheduled medical test for the patient and a change to a medication prescription for the patient.