Organic Catatonic Disorder:
Organic catatonic disorder is a disorder of diminished (stupor) or increased (excitement) psychomotor activity associated with catatonic symptoms. The extremes of psychomotor disturbance may alternate. 
According to the ICD-10 (F06.1) disorder of diminished (stupor) or increased (excitement) psychomotor activity associated with catatonic symptoms. The extremes of psychomotor disturbance may alternate.  The presence of other catatonic symptoms and signs increases the conﬁdence in the diagnosis. 
Sign & Symptoms:
1. Mutism: Complete absence of speech.
2. Rigidity: Maintenance of a rigid posture against efforts to be moved.
3. Negativism: An apparently motiveless resistance to all commands and attempts to be moved, or doing just the opposite.
4. Posturing: Voluntary assumption of an inappropriate and often bizarre posture for long periods of time.
5. Stupor: Akinesis (no movement) with mutism but with evidence of relative preservation of conscious awareness.
6. Echolalia: Repetition, echo or mimic king of phrases or words heard.
7. Echopraxia: Repetition, echo or mimic king of actions observed.
8. Waxy ﬂexibility: Parts of body can be placed in positions that will be maintained for long periods of time, even if very uncomfortable; ﬂexible like wax.
9. Ambitendency: Due to ambivalence, conﬂicting impulses and tentative actions are made, but no goal directed action occurs, e.g. on asking to take out tongue, tongue is slightly protruded but taken back again
10. Other signs: Such as mannerisms, stereotypies (verbal and behavioural), automatic obedience (commands are followed automatically, irrespective of their nature) and verbigeration (incomprehensible speech). 
1. Neurological Disorders:
- Post-encephalitic parkinsonism
- Limbic encephalitis
- Surgical procedures on basal ganglia
- Neoplasms in diencephalon, frontal lobe and limbic system
- Subacute sclerosing panencephalitis (SSPE)
- General paresis of insane (GPI)
- Petitmal status
- Post-ictal phase of epilepsy
- Subdural haematoma
- Cerebral malaria
- Cortical venous thrombosis
2. Systemic and Metabolic Disorders:
- Diabetic ketoacidosis
- Acute intermittent porphyria
- Hyperparathyroidism causing hypercalcaemia
- Hepatic encephalopathy
- Systemic lupus erythematosis
- Membranous glomerulonephritis
3. Drugs and Poisoning:
- Organic alkaloids
- ACTH (therapeutic doses)
- Illuminating gas
- Ethyl alcohol (large doses)
- CO poisoning
- Lithium toxicity
- Phencyclidine (large doses)
4. Psychiatric Disorders:
- Catatonic schizophrenia
- Depressive stuporManic stupor
- Periodic catatonia
- Conversion and dissociative disorder
- Reactive psychosis
- During hypnosis. 
According to the ICD-10(F06.1), the following features are required for the diagnosis of organic catatonic disorder, in addition to the general guidelines for the diagnosis of other organic mental disorders, described earlier:
1. Stupor (diminution or complete absence of spontaneous movement with partial or complete mutism, negativism, and rigid posturing).
2. Excitement (gross hypermotility with or without a tendency to assaultiveness).
3. Mixed (shifting rapidly and unpredictably from hypo- to hyperactivity). 
1. Treatment of the underlying cause, if amenable to treatment.
2. Symptomatic treatment with low dose of a short acting benzodiazepine (e.g. Lorazepam), or electroconvulsive therapy (if needed). Antipsychotics should usually be avoided as they can make catatonic features worse; however small doses of atypical antipsychotics such as Risperidone, Olanzapine, Aripiprazole or Quetiapine can be used with care.