Pharmacology of the Central Nervous SystemSedatives, Hypnotics, Affective, and Antipsychotics
Teaching and Learning Objectives Sedative-Hypnotic and Antianxiety Drugs• Name the 2 major types of sedative- hypnotic and antianxiety drugs.• Describe the general mechanism of action of all 2 of the types of drugs.• Discuss problems and adverse effects of these types of drugs.• Compare/contrast sedative-hypnotic and antianxiety drugs.
Teaching and Learning Objectives• List the major types of antianxiety drugs• Describe the problems and adverse effects of these drugs• Discuss the implications for the PT management of patients taking sedative- hypnotic and antianxiety drugs• Modify PT interventions for persons taking these drugs
Teaching and Learning Objectives Antidepressive and Bipolar Drugs• Describe the clinical signs of depression• Describe the theoretical neurotransmitter basis of depression• Explain the mechanism of action of antidepressive drugs• List the 3 major groups of antidepressive drugs
Teaching and Learning Objectives• Describe the mechanism of action of the 3 groups of antidepressant drugs• Discuss the problems and adverse effects of the 3 groups• Explain the use of antidepressant drugs in the management of chronic pain• Define Bipolar Disorders• Discuss the use of Lithium for bipolar disorders
Teaching and Learning Objectives• Discuss the special concerns for rehabilitation in patients taking antidepressant and bipolar drugs• Modify PT management of patients taking antidepressant and bipolar drugs
Teaching and Learning Objectives Antipsychotic Drugs• Define Psychosis and list the associated symptoms• Describe the theoretical neurotransmitter basis of psychosis• Explain the mechanism of action of antipsychotic drugs• Explain the major difference in traditional and atypical antipsychotic drugs
Teaching and Learning Objectives• Explain the use of antipsychotic drugs in persons with dementia• Define “extrapyramidal” symptoms• Recognize extrapyramidal symptoms• Describe Tartive Dyskinesis• List non-motor side effects of antipsychotic drugs• Describe special PT rehabilitation concerns in persons taking antipsychotic medications• Modify PT strategies for patients taking antipsychotic drugs
Sedative-Hypnotic Drugs• Used to relax ( low doses)• Used to promote sleep (higher doses)• Very commonly used by inpatients and outpatients.• 2 general categories of drugs Benzodiazepines NonbenzodiazepinesAll sedative/hypnotic drugs act as GABA receptor agonists, ie., increase chloride entry to the post- synaptic membrane, thus inhibiting the synapse.
BenzodiazepinesTherapeutic effects:– Sedation– Sleep– Anxiety reduction• Diazepam (Valium) most well known example
Side Effects• Dependence- Withdrawal symptoms associated with cessation of the drug• Tolerance- Necessity of increasing dosage to attain therapeutic effect• Day after residual effects- especially important for PTs to be aware of.• Drowsiness and decreased motor performance day after taking drug• Anteriorgrade amnesia- poor recall of details and events for a period of time after taking the drug
Nonbenzodiazepines• Barbituates- hypnotics Uncommonly used today due to risk of overdose, tolerance and dependence.Tolerance- more drug necessary for an effectDependence- withdrawal symptoms• Newer Drugs – Zolpidem (Ambien) and Zaleplon (Sonata) • Sedative/hypnotic effects • Less risk of overdose , tolerance and dependence
Antianxiety Drugs• Benzodiazepines Used at lower doses for antianxiety than as for sedative/hypnotic effects.• Nonbenzodiazepines Buspirone (BuSpar)- Acts through the serotonin receptor as an agonist, not GABA. Least risk of tolerance, dependency and sedation effects of available antianxiety drugs.
PT Implications of Sedative/Hypnotic/Antianxiety Drugs Assignment• May be helpful in gaining patient cooperation with therapy.• May be detrimental if patient drowsy, so scheduling therapy should take into account the time of maximal effect of sedation.• May increase the risk of falls, so that balance training and environmental modifications may be provided by the therapist.• Non-pharmacologic measures to reduce anxiety and insomnia such as therapeutic massage, exercise, and relaxation techniques may avoid the need or reduce the effective dose of these drugs. (Instructor may make a cloud display containing all of the answers and post for
Neurotransmitter Basis of Depression• http://www.metacafe.com/watch/3486985/how_s sris_and_mao_inhibitors_work/?fb_xd_fragment #?=&cb=f1d74aef3bf2f9d&relation=parent.paren t&transport=fragment&type=resize&height=200& ackData[id]=1• Drugs that prolong the action of serotonin and dopamine, decrease sensitivity to these neurotransmitters by down regulating the excessive stimulation which is thought to cause depression.
3 Types of Antidepressant Drugs• Tricyclics Amitriptyline, Imipramine• Monoamine Oxidase Inhibitors (MAOI)• Serotonin Reuptake Inhibitors (SSRI) - Prozac, Paxil, ZoloftSince all of these drugs act by desensitization of the synapse to the neurotransmitters, they often require 2-4 weeks for therapeutic effect to occur.
Adverse Effects• SSRI Lesser degree of sedation, anticholinergic, and cardiovascular effects than tricyclics and MAOI. Serotonin Syndrome- Life threatening http://www.medclip.com/index.php?page= videos§ion=view&vid_id=105700
Bipolar Disorders• Pendulum-like swings between mania and depression.• Treatment designed to prevent the swings by dampening neuronal (synaptic) transmission.• Lithium is drug most often used. Tendency to accumulate in body reaching toxic levels.• Side effects include tremor, weakness, confusion, ataxia, dysarthria, nystagmus, increased DTRs, choreoathetoid movements, coma and death
Psychosis• Thought process disturbance with impaired perception of reality.• Schizophrenia most common form Effects 1% of world population Symptoms include bizarre delusions, hallucinations, poor social relations and self-care. 70-80% genetic tendency.
Antipsychotic Drugs• Traditional antipsychotics- Haldol, Prolixin, Thorazine, Mellaril Side effects include extrapyramidal signs, sedative and anticholinergic effects.• Atypical antipsychotics- First line drugs of choice Significantly fewer (lesser) side effects than traditional drugs Often used in Alzheimers and other persons with dementia to control agitation and aggression.
Side Effects of Antipsychotic Drugs http://www.youtube.com/watch?v=Ki9t2sSBFmA