olanzapine is serotonin dopamine antagonist which controls positive symptoms in schizophrenia by suppressing dopamine in mesolimbic region with less deterioration of negative symptoms and extrapyramidal syndrome . the disorder may be hereditary or due to secondary factors like physical trauma , infection , poisoning ( e.g. , lead poisoning ) or reaction to neuroleptics ( tardive dystonia ) . cervical dystonia ( spasmodic torticollis ) causes the head to rotate to one side or toward chest , or back , or a combination of this posture . tardive dystonia has an earlier mean onset age than that of many other dystonic disorders . young patients generally first exhibit tardive dystonia symptoms in the lower limbs , while older patients usually experience their first symptoms in the facial region . the prevalence of tardive dystonia is 0.5 to 21.6% in patients who are treated with neuroleptics . a male patient aged 27 years presented in our psychiatry clinic with history of alcohol intake from last 6 years . patient started with 90 ml occasionally and gradually reached up to 500 - 750 ml daily to get the same desired effect . he tried many times to control his drinking pattern but failed because of severe withdrawal symptoms . history of marital disharmony and frequent fights at work was present but never had any medical or legal complications . on mse , patient was conscious , cooperative , oriented , moderately built and nourished , eye contact and rapport established . insight was grade v. patient was thoroughly assessed , diagnosed as f 10 ( icd-10 ) and admitted in psychiatry ward for management . thiamine 100 mg bid . on third day evening , patient turned irritable with fluctuating consciousness . patient was diagnosed as delirium tremens and injection olanzapine 10 mg i / m were given . after 4 hours patient became restless and had spasmodic contraction of neck and head turned toward left side ( acute cervical dystonia ) with the repetitive sustained contractions of the orbicularis oculi ( tardive blepharospasm ) . treatment for dystonia continued with lorazepam 2 mg and trihexyphenidyl 6mg / day but no improvement was seen . then neurological opinion was taken and patient was put on baclofen 20mg / day and dose was raised to 40mg / day over a period of 4 weeks . patient was discharged after 30 days of admission on baclofen 40 mg , lorazepam 2 mg , trihexyphenidyl 6 mg and tetrabenazine 75mg / day . patient showed 50 to 60% improvement in his condition subjectively and objectively after 2 years of regular treatment . olanzapine is used to relief symptoms in schizophrenia , dysfunctional mood condition in bipolar to control agitation and extreme excitement , too aggression and agitation in substance use disorder . for handling emergency situations parental use of olanzapine ( intramuscular ) rapid - acting intramuscular formulation of olanzapine has a more rapid rate of absorption , as shown by higher maximal concentration ( cmax ) ( two- to five folds ) and an earlier time to cmax ( 30minutes vs 4 hours ) than oral formulation . tardive dystonia often develops at higher rates in patients receiving neuroleptic agents for long period than one treated for shorter period of time . there are no definitively determined factors why some patients develop this condition while others do not . olanzapine appears to have a higher d2-receptor occupancy at therapeutic doses than other serotonin and dopamine antipsychotics . although there are reports of dystonia with oral olanzapine , the present report shows that dystonic reactions can also occur with intramuscular olanzapine in young adults . in a survey of 555 psychiatric patients , yassa et al found a prevalence rate of 34% for oral tardive dyskinesia and only 1.4% for tardive dystonia . similarly , friedman et al . found a prevalence rate of only 1.5% among 352 hospitalized psychiatric patients . one recent study by sethi et al indicated a prevalence rate of 21% for tardive dystonia among veterans institutionalized long term . pathophysiology of acute dystonic reactions involves increased dopamine synthesis and release , especially as neuroleptic levels in the blood and brain decline by use of sdas . this could have accounted for development of dystonia ( torticollis type ) in the patient reported as above . tardive dystonia has an earlier mean onset age than that of many other dystonic disorders . young patients generally first exhibit tardive dystonia symptoms in the lower limbs , while older patients usually experience their first symptoms in the facial region . young age with faster drug elimination , male sex and presence of delirium in substance dependence syndrome ( alcohol ) might be possible risk factors in our case experiencing dystonic reactions early in the course of treatment . although the exact mechanism by which these medications cause tardive dystonia is not clearly understood , it is believed that the disorder may develop when dopamine receptor blockers cause neurons to become hypersensitive to chemicals released by the drugs . some research suggests that the medications may act as triggers in patients already predisposed to dystonia . clinicians should consider the possibility of the development of tardive dystonia in susceptible individuals even at low doses insufficient to obtain a true antipsychotic action . further reports and well - designed trials are necessary considering the potential use of intramuscular olanzapine in controlling agitation and delirious state in case of alcohol dependent subjects . this calls for a very cautious approach for its use in young age group as motor side effects are most visible and distressing side effects of psychotropic drugs . until further data are available , careful assessments are warranted for movement disorders in patients with substance dependence disorder who are receiving olanzapine .
olanzapine is an atypical antipsychotic drug which is available in oral and injectable forms that is used for treatment of various psychiatric disorders . 
 we report a rare case of tardive dystonia after receiving single dose of olanzapine ( 10 mg ) in parental form . 
 clinicians should be very vigilant regarding this rare side effect with use of olanzapine in clinical practice .