Cyclic triazo and diazo sodium channel blockers

A method of treating a disorder comprising administering to a subject in need thereof a compound of general formula (I), or a salt or solvate thereof,

• in which:
• X and Y are each N;
• Z is a single bond or an optionally substituted linking group;
• R1 is hydrogen, or a substituent group, or the Y nitrogen is unsubstituted;
• R2 is amino or a substituent group;
• N* is amino when R1 is hydrogen or ═NH when R1 is a substituent group;
• or
• N* is a group NRaRb where Ra and Rb are independently H or an alkyl group;
• or
• N* is an optionally substituted piperazinyl ring;
• and
• A is an optionally substituted phenyl group or an optionally substituted sulphur containing heterocycle;
• wherein the disorder is epilepsy, multiple sclerosis, glaucoma and uveitis, cerebral traumas and cerebral ischaemias, stroke, head injury, spinal cord injury, surgical trauma, neurodegenerative disorders, motorneurone disease, Alzheimer's disease, Parkinson's disease, chronic inflammatory pain, neuropathic pain, migraine, bipolar disorder, mood, anxiety and cognitive disorders, schizophrenia, or trigeminal autonomic cephalalgias.