1. Pharmacological emergencies
Jacob Alexander
February 2016
TAPPP

2. Range of side effects from commonly prescribed medication
Medication Induced Movement Disorders
Serotonergic Syndrome
Drug Induced Weight Gain
Drug induced dysphoria, negative syndrome like symptoms
Drug related anticholinergic side effects
Drug induced cardiac complication- QTc prolongation

3. Medication Induced Movement Disorders

4. Extra pyramidal system
Anatomical
Neural Network that is part of the motor system
Reticular formation of the pons and the medulla
Nigrostriatal pathway
Basal Ganglia
Cerebellum
Cerebral cortex- motor and sensory areas
Functional
Causes involuntary reflexes and movements
Locomotion
Complex movements
Postural control

5. Extrapyramidal Tracts

6. Extrapyramidal Side Effects (EPSEs)
The first generation (conventional) antipsychotics may cause significant extrapyramidal side effects, more so than the second generation antipsychotic agents.
Risperidone and Ziprasidone more likely to cause EPSEs amongst second generation antipsychotic agents
EPSEs require careful assessment and management

7. Objectives Objectives Early Identification
Encourage and alleviate anxiety for patient and carers
Be able to explain causes
Be able to explain treatments
Be able to choose/ prescribe treatment options

8. Types of EPSEs Dystonia Parkinsonism Akathisia Tardive Dyskinesia
Acetylcholine-Dopamine dysregulation syndromes

9. EPSEs time to onset Immediately after use
48 hours from initiation of drug or increase in dose
3 weeks from initiation of drug or increase in dose
6 months or more of use
Hypersensitivity reactions
Dystonia
Parkinsonian symptoms
Tardive dyskinesia / dystonia/ akathisia
Akathisia

10. Dystonia
Occurs usually within 48 hours of initiation of the medication
Involves bizarre and severe muscle contractions
Can be painful and frightening
Characterized by odd posturing and strange facial expressions

11. Drug-induced Parkinsonism
Usually occurs after 3 or more weeks of treatment
Characterized by:
Cogwheeling rigidity
Tremors
Rhythmic oscillations of the extremities
Pill rolling movement of the fingers

12. Akathisia Usually occurs after 3 or more weeks of treatment
Subjectively experienced as desire or need to move
Described as feeling like jumping out of the skin
Mild: a vague feeling of apprehension or irritability
Severe: an inability to sit still, resulting in rocking, running, or agitated dancing

13. Tardive Dyskinesia Tardive Dyskinesia
Usually occurs late in the course of long-term treatment
Characterized by abnormal involuntary movements (lip smacking, tongue protrusion, foot tapping)
Often irreversible

14. Complications of Tardive Dyskinesia
Inability to wear dentures
Impaired respirations
Weight loss
Impaired gait
Impaired posture

15. Dopamine-Acetylcholine Imbalance in the Extrapyramidal System
A rare side effect
Characterized by hallucinations, dry mouth, blurred vision, decreased absorption of antipsychotics, decreased gastric motility, tachycardia, and urinary retention
Neuroleptic Malignant Syndrome

16. Methods to Improve Assessment of EPSEs
Use rating scales.
AIMS
Simpson Neurological Rating Scale
Videotape the exam for comparison at a later date

17. Treatment Treatment of EPSEs Titrate dose
Switch to AP less likely to cause extra-pyramidal side-effects
Evaluate need for EPSE causing other meds- metaclorpromide, amoxapine, SSRIs
Anticholinergic agents- benztropine, trihexyphenidyl, benadryl
Akathisia- benzodiazepines and beta blockers

18. http://youtu.be/pSXzuCNlI6Q akathisia
dystonia
catatonia
tardive dyskinesia
parkinsonism

19. Serotonergic Syndrome

20. Drugs implicated in severe serotonin syndrome
Mechanism
L-tryptophan
SSRIs
TCAs
MOAIs
Pethidine
Tramadol
LSD
Buspirone
Amphetamines and anorectics
Atypical Antidepressant
St John’s wort
Lithium
Serotonin precursor
Inhibits serotonin reuptake
Inhibit Metabolism of 5-HT
Serotonin agonist
Partial serotonin agonist
Increased 5_HT release and decreased reuptake
Various
All of the above?
Unknown

21. Clinical features of serotonin syndrome
Cognitive
Autonomic
Neuromuscular
Confusion, agitation, hypomania, hyperactivity, restlessness
Hyperthermia, sweating, tachycardia, hypertension, mydriasis, flushing, shivering
Clonus(spontaneous/inducible/ocular), hyperreflexia, hypertonia, ataxia, tremor
Hypertonia and clonus are always symmetrical and are often much more dramatic in the lower limbs

22. Sternbach Criteria Mental state changes (confusion, hypomania)
Agitation
Myoclonus
Hyperreflexia
Diaphoresis
Shivering
Tremor
Diarrhoea
Inco-ordination
Fever
Hunter Serotonin Toxicity Criteria

23. Treatment Cessation of offending agent
Mild to moderate – resolves spontaneously in hours
Supportive care , temperature management, benzodiazepines
In severe cases- cyproheptadine, propranolol, chlorpromazine

24. Dealing with drug induced QTc prolongation
<400 ms (men)
<470 ms (women)
>500 ms (men or women)
No action required, referral to cardiologist based on specific concerns
Consider:
Dose reduction
Medication change
Repeat ECG
Cardiology referral?
Stop suspected causative agent and switch to alternative that is less cardio offensive
Refer to cardiologist as a matter of priority
Abnormal T Wave Morphology- review treatment: reduce dose, switch to drug of lower effect, cardiologist referral