Extrapyramidal reaction: Difference between revisions
(Text replacement - "OR" to "'''OR'''") |
(Add MedicationDose entries for diphenhydramine, benztropine) |
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**hours to days after drug initiation | **hours to days after drug initiation | ||
**reversible | **reversible | ||
**Acute [[ | **Acute [[dystonic reaction]] | ||
***involuntary, uncoordinated skelatal muscle contraction | ***involuntary, uncoordinated skelatal muscle contraction | ||
**Akathisia | **Akathisia | ||
| Line 15: | Line 15: | ||
*Parkinsonism | *Parkinsonism | ||
**onset weeks to months after starting medication | **onset weeks to months after starting medication | ||
**similar presentation to [[Parkinson's disease]] (e.g. cogwheel | **similar presentation to [[Parkinson's disease]] (e.g. cogwheel rigidity, pill-rolling tremor, shuffling gait, bradykinesia) | ||
*Tardive dyskinesia | *[[Tardive dyskinesia]] | ||
**usually irreversible or only partially reversible | **usually irreversible or only partially reversible | ||
**associated with prolonged use of antipsychotics | **associated with prolonged use of antipsychotics | ||
** | **stereotyped, repetitive facial movements (e.g. tongue protrusion, grimacing, lip smacking) | ||
==Differential Diagnosis== | ==Differential Diagnosis== | ||
{{Movement disorder DDX}} | |||
==Evaluation== | ==Evaluation== | ||
| Line 37: | Line 29: | ||
*Stop or reduce offending agent | *Stop or reduce offending agent | ||
**may need to discuss with psychiatrist to prescribe new medication or for recs on taper | **may need to discuss with psychiatrist to prescribe new medication or for recs on taper | ||
*Acute dystonia, akasthisia, parkinsonism | *Acute [[dystonic reaction|dystonia]], akasthisia, parkinsonism | ||
**[[diphenhydramine]] 25-50mg PO or IV | **[[diphenhydramine]] 25-50mg PO or IV | ||
**'''OR''' [[benztropine]] 1-2mg PO or IV/IM | **'''OR''' [[benztropine]] 1-2mg PO or IV/IM | ||
**continue PO antihistamines for 2 days after stopping antipsychotic | **continue PO antihistamines for 2 days after stopping antipsychotic | ||
**+/- [[benzodiazepines]] | **+/- [[benzodiazepines]] | ||
*Tardive dyskinesia | *[[Tardive dyskinesia]] | ||
**may only be partially reversible, so minimize occurrence, stop or reduce offending agent promptly | **may only be partially reversible, so minimize occurrence, stop or reduce offending agent promptly | ||
**Do NOT give anticholinergics, will exacerbate symptoms | **Do NOT give anticholinergics, will exacerbate symptoms | ||
==Disposition== | ==Disposition== | ||
==Medication Dosing== | |||
{{MedicationDose | |||
| drug = Diphenhydramine | |||
| dose = 25-50mg PO or IV | |||
| route = PO/IV | |||
| context = Anticholinergic for acute dystonia/akathisia | |||
| indication = Extrapyramidal reaction | |||
| population = Adult | |||
}} | |||
{{MedicationDose | |||
| drug = Benztropine | |||
| dose = 1-2mg PO or IV/IM | |||
| route = PO/IV/IM | |||
| context = Anticholinergic for acute dystonia/akathisia | |||
| indication = Extrapyramidal reaction | |||
| population = Adult | |||
}} | |||
==See Also== | ==See Also== | ||
Latest revision as of 21:16, 20 March 2026
Background
- Adverse effect of antipsychotics.
- More common with high-potency typical antipsychotics, but can also occur with atypical agents
- Due to antagonism of dopamine-2 receptors in basal ganglia
Clinical Features
- Early-onset syndromes
- hours to days after drug initiation
- reversible
- Acute dystonic reaction
- involuntary, uncoordinated skelatal muscle contraction
- Akathisia
- subjective sensation of intense motor restlessness
- may be misdiagnosed as manifestation of psychiatric disease
- Parkinsonism
- onset weeks to months after starting medication
- similar presentation to Parkinson's disease (e.g. cogwheel rigidity, pill-rolling tremor, shuffling gait, bradykinesia)
- Tardive dyskinesia
- usually irreversible or only partially reversible
- associated with prolonged use of antipsychotics
- stereotyped, repetitive facial movements (e.g. tongue protrusion, grimacing, lip smacking)
Differential Diagnosis
Movement Disorders and Other Abnormal Contractions
- Chorea
- Neuroleptic malignant syndrome
- Serotonin syndrome
- Hypocalcemia
- Strychnine toxicity
- Acute tetanus
- Parkinson's disease
- Mono amine oxidase inhibitor toxicity
- Phencyclidine toxicity
- Anti-NMDA receptor encephalitis
- Huntington disease
- Wilson's disease
- CVA
- Schizophrenia
- Psychotic agitation
- Dementia
- Lewy body dementia
- Vascular dementia
- Frontotemporal dementia
- Dystonic reaction
- Extrapyramidal reaction
- Torticollis
- Idiopathic movement disorder
Evaluation
Management
- Stop or reduce offending agent
- may need to discuss with psychiatrist to prescribe new medication or for recs on taper
- Acute dystonia, akasthisia, parkinsonism
- diphenhydramine 25-50mg PO or IV
- OR benztropine 1-2mg PO or IV/IM
- continue PO antihistamines for 2 days after stopping antipsychotic
- +/- benzodiazepines
- Tardive dyskinesia
- may only be partially reversible, so minimize occurrence, stop or reduce offending agent promptly
- Do NOT give anticholinergics, will exacerbate symptoms
Disposition
Medication Dosing
Diphenhydramine 25-50mg PO or IV PO/IV Benztropine 1-2mg PO or IV/IM PO/IV/IM