* TARDIVE DYSKINESIA IS THE MOST COMMON DELAYED ( LATE) COMPLICATION OF ANTIPSYCHOTIC MEDICATION * IT IS CHARACTERISED BY PURPOSELESS, INVOLUNTARY FACIAL AND LIMB MOVEMENTS TARDIVE DYSKENYSIS * MUSCULAR DYSTONIA : - IS CHARACTERISED BY BIZZARE MUSCLE SPASMS SPECIALLY AFFECTING LINGUOFASCIAL MUSCLES - GRIMACING ETC.OCCURS WITHIN FEW HOURS OF A SINGLE DOSE AT MOST MOST WITHIN A WEEK. MUSCULAR DYSTONIA THUS W HILE FACIAL MOVEMENTS CAN BE A FEATURE OF BOTH TARDIVE DYSKINESIA AND MUSCULAR DYSTONIA, THOSE DEVELOPING AS LATE AS 5 YEARS AFTER INSTITUTION OF TREATMENT ARE LIKELY TO BE DUE TO BE DUE TO TARDIVE DYSKINESIA. * AKATHASIA : REFERS TO REST LESSNESS / F EELING OF DISCOMFO / APPARENT AGITATION FACIAL MOVEMENTS ARE NOT A FEATURE. AKATHASIA * MALIGNANT NEUROLEPTIC SYNDROME : IS CHARACTRISED BY RIGIDITY, IMMOBILITY, FEVER, FLUCTUATING BP AND HEA RATE. FACIAL MOVEMENTS ARE NOT A FEATURE REF : HARRISONS 20TH ED