Pharmacology Module 7 PDF

PRELIMS: NCMA 216 (PHARMACOLOGY) CLASSIFICATIONS OF DRUGS DOPAMINE - MODULE #7: DRUGS ACTING ON THE AFFECTING THE CNS. Function: Pleasure CVS | VENJULLIAN. 1. Anxiolytic and Hypn...

PRELIMS: NCMA 216 (PHARMACOLOGY) CLASSIFICATIONS OF DRUGS DOPAMINE - MODULE #7: DRUGS ACTING ON THE AFFECTING THE CNS. Function: Pleasure CVS | VENJULLIAN. 1. Anxiolytic and Hypnotic Agents — Feelings of pleasure, addiction, movement and 2. Antidepressant Agents motivation. People repeat behaviors that lead to DRUGS ACTING ON THE CENTRAL AND 3. Psychotherapeutic Agents dopamine release. PERIPHERAL NERVOUS SYSTEMS. 4. Anti - seizure Agents 5. Anti - parkinsonism Agents SEROTONIN ACTION POTENTIAL - this is a rapid change in the Function: Mood membrane potential that explains how impulses are NEUROTRANSMITTERS: — Contributes to well-being and happiness. conducted along the nerves ADRENALINE/EPINEPHRINE Helps sleep cycle and digestive system ANXIETY - feeling of fear, tension, or apprehension Function: Fight or Flight regulation. from known or unknown reasons — Produced in stressful situations. Increases — Affected by exercise. heart rate and blood flow, leading to physical DEPRESSION - affective disorders characterized by boost and heightened awareness. extreme sadness, hopelessness, and disorganization NORADRENALINE/NOREPINEPHRINE MANIA - characterized by period of extreme over Function: Concentration activity and excitement — Affects attention and responding actions in the NEUROTRANSMITTERS - chemicals in the nervous brain. system that help in the transmission of impulses — Contract blood vessels, increasing blood flow. PALLIATIVE TREATMENT - control of signs and GAMMA-AMINOBUTYRIC ACID (GABA) symptoms of the disease Function: Calming — Calms firing nerves in the central nervous PARKINSON'S DISEASE - degenerative disease of the nervous system characterized by lack of system. neurotransmitter called Dopamine — High levels improve focus, low levels cause anxiety. SCHIZOPHRENIA - most common type of psychotic — Also contributes to motor control and vision. disorder that may cause impairment of function of an individual in the society ACETYLCHOLINE Function: Learning SEIZURE - abnormal and excessive impulse transmission in the brain — Involved in thought, learning, and memory. Activates muscle action in the body. Also SYNAPTIC TRANSMISSION - conduction of associated with attention and awakening. impulses across the junction between neurons ANXIOLYTIC AND HYPNOTIC AGENTS. BARBITURATES USED AS ANXIOLYTIC BENZODIAZEPINES USED AS ANXIOLYTIC OR OR HYPNOTICS HYPNOTICS STATES AFFECTED BY ANXIOLYTIC AND HYPNOTIC DRUGS BARBITURATES - were once the sedative or BENZODIAZEPINES, the most frequently used hypnotic drugs of choice. anxiolytic drugs, prevent anxiety without causing ANXIETY - a feeling of tension, nervousness, — adverse effects greater with these drugs than much associated sedation. apprehension, or fear that usually involves with newer sedative/ hypnotic drugs unpleasant reactions to a stimulus, whether actual Examples: In addition, they are less likely to cause physical or unknown. 1. Phenobarbital (Luminal) dependence than many of the older — S/SX of the sympathetic stress reaction which 2. Secobarbital (Seconal) sedatives/hypnotics that are used to relieve 3. Amobarbital (Amytal Sodium) anxiety. may include sweating, fast heart rate, rapid breathing, and elevated blood pressure. Therapeutic Actions and Indications Therapeutic Actions and Indications — can cause sedation, hypnosis, anesthesia, and, — indicated for the treatment of the following SEDATION - loss of awareness and reaction to in extreme cases, coma. conditions: anxiety disorders, alcohol environmental stimuli — indicated for the relief of the signs and withdrawal, hyperexcitability and agitation, and — conditions may be desirable in patients who symptoms of anxiety and for sedation, insomnia, preoperative relief of anxiety and tension to aid are restless, nervous, irritable, or overreacting to pre-anesthesia, and the treatment of seizures in balanced anesthesia. stimuli. — Parenteral forms: used for the treatment of Examples: acute manic reactions and many forms of seizures 1. Diazepam HYPNOSIS - the extreme state of sedation, in 2. Lorazepam which the person no longer senses or reacts to 3. Clonazepam Contraindications and Cautions: incoming stimuli. — Pregnant women — Clients with hepatic and renal dysfunction Contraindications and Cautions: DRUGS FOR ANXIETY. — Clients with allergy to benzodiazepines, — are called Anxiolytic Drugs or Sedative psychosis, clients with acute narrow angle Adverse Effects: Hypnotic Agents glaucoma, shock, acute alcohol intoxication — CNS depression paradoxical excitement anxiety and hallucinations. which may exacerbate the depressant effects of 1. Barbiturates the drugs. — Gastrointestinal signs and symptoms like 2. Benzodiazepines — Pregnancy as this is known to possibly cause nausea, vomiting, constipation, diarrhea and 3. Non - Benzodiazepines cleft lip or palate, inguinal hernia, cardiac epigastric pain. — Cardiovascular effects include bradycardia, defects, microcephaly or pyloric stenosis if taken Mechanism of Action - to enhance the effect of during the first trimester. hypotension and syncope GABA (Gamma Amino Butyric Acid) — Elderly or debilitated patients and those with hepatic and renal functions Adverse Effects: NURSING CONSIDERATIONS FOR Depression occurs due to decreasing — Sedation — Drowsiness ANXIOLYTIC AND HYPNOTIC AGENTS. neurotransmitters, norepinephrine, serotonin and — Depression — Lethargy 1. Do not administer intraarterially because of dopamine. — Constipation — Orthostatic hypotension possible serious arteriospasm and gangrene — Decreasing neurotransmitter in the limbic — Urinary retention — Dysrhythmias may develop system which may happen due possibly to: — Blood dyscrasias — Phlebitis 2. Do not mix IV drugs with other drugs 1. Overused of neurotransmitters — Anticholinergic effects like drying of mouth 3. Give parenteral forms if oral forms are not (Norepinephrine, Dopamine and Serotonin) — Withdrawal syndrome may occur with abrupt feasible and switch to oral which is safer 2. Increase effect of MonoAmine Oxidase cessation characterized by nausea, headache, 4. Give IV drugs slowly to avoid hypotension (MAO) enzyme vertigo, malaise and headache. effects 3. Increase reuptake of neurotransmitter back 5. Promote safety measures to presynaptic neuron OTHER ANXIOLYTIC/HYPNOTIC DRUGS 6. Monitor hepatic and kidney function Other drugs are used to treat anxiety or to 7. Taper dose of drugs gradually ANTIDEPRESSANT DRUGS - used today produce hypnosis that do not fall into either the 8. Provide comfort measures to help patient counteract the effects of neurotransmitter benzodiazepine or the barbiturate group. tolerate the effects of drugs deficiencies (alter the concentration of 9. Provide thorough health teaching about drug neurotransmitters) in three ways. ANTIHISTAMINES (Promethazine[Phenergan], effects and adverse reactions 1. inhibit the effects of MAO, leading to Diphenhydramine[Benadryl] ) 10. For overdose of Benzodiazepine, Flumazenil increased NE or 5HT in the synaptic cleft. — can be very sedating in some people. must be ready as its antidote. 2. block reuptake by the releasing nerve, — used as preoperative medications and leading to increased neurotransmitter levels postoperatively to decrease the need for ANTIDEPRESSANT AGENTS. in the synaptic cleft. narcotics. — Depression is a very common affective 3. regulate receptor sites and the breakdown of disorder involving feelings of sadness that are neurotransmitters, leading to an BUSPIRONE (BuSpar) much more severe and longer lasting than the accumulation of neurotransmitters in the — a newer antianxiety agent, has no sedative, suspected precipitating event, and the mood of synaptic cleft. anticonvulsant, or muscle relaxant properties, affected individuals is much more intense. — reduces the signs and symptoms of anxiety Sad or depressed mood ANTIDEPRESSANTS ARE CLASSIFIED without many of the CNS effects Loss of pleasure or interest INTO THREE GROUPS: Insomnia (or sometimes hypersomnia) BETA BLOCKERS (Propranolol/Metoprolol) Anorexia (or sometimes hyperphagia) 1. Tricyclic antidepressants (TCAS) — Decreases sympathetic effect to lessen signs Mental slowing and loss of concentration 2. MonoAmine Oxidase Inhibitors (MAOIs) and symptoms of anxiety Feelings of guilt, worthlessness, helplessness 3. Selective serotonin reuptake inhibitors Thoughts of death and suicide and/or overt (SSRIs) ZOLPIDEM suicidal behavior — Used to treat insomnia. Metabolized in the Symptoms must be present most of the day, Other drugs that are used as antidepressants liver and excreted in the urine nearly every day, for at least 2 weeks similarly increase the synaptic cleft concentrations of these neurotransmitters 1. TRICYCLIC ANTIDEPRESSANTS (TCA’s) Contraindication: SSRI’s: Patient Education Tricyclic antidepressants block the neuronal — Tyramine is the building block of — Effects take 10-21 days reuptake of two monoamine transmitters: norepinephrine and is commonly found in foods — Wean SSRIs when discontinuing them. norepinephrine (NE) and serotonin. that are aged. — Give with food at bedtime to minimize — leads to accumulation of these — MAOIs inhibit monoamine oxidase, so the anticholinergic effects, unless sleep is disturbed neurotransmitters in the synaptic cleft and body cannot rid itself of excess norepinephrine. — May increase suicidal tendency early in the increased stimulation of post-synaptic receptors — Raised levels of norepinephrine may lead to a treatment. Examples: hypertensive crisis after consumption of certain 1. Amitriptyline (Elavil) types of tyramine-containing foods or drinks. SSRI’s: Side Effects 2. Imipramine (Tofranil) 1. Insomnia, anxiety, and nervousness 3. Clomipramine (Anafranil) 4. Nortriptyline (Aventyl) 3. SELECTIVE SEROTONIN REUPTAKE 2. Headache 5. Amoxapine (Asendin) INHIBITORS (SSRI’s) 3. Sexual dysfunction — the newest group of antidepressant drugs, 4. Weight gain, nausea, Gl distress, dry mouth — TCAs can cause confusion in the elderly. specifically block the reuptake of serotonin, with — Common side effects include anticholinergic little to no known effect on NE. SEROTONIN SYNDROME effects and weight gain. — Do not have the many adverse effects Life threatening: Autonomic Instability associated with TCAs and MAOls, they are a Adverse Effects: better choice for many patients. Neuromuscular Effects: C - Cardiovascular effects Example: — Myoclonus — Tremor 1. Fluoxetine (Prozac) the first SSRI — Grinding teeth — Rhabdomyolysis A - Anticholinergic effects 2. Citalopram (Celexa) S - Sedation 3. Duloxetine (Cymbalta) H- Hypotension or Hypertension 4. Escitalopram (Lexapro) newest SSRI , Autonomic instability Effects: Fluvoxamine (Luvox) — Fever — Sweating, 2. MONOAMINE OXIDASE INHIBITORS 5. Paroxetine (Paxil) — Hyperthermia — Tachycardia (MAOI’s) 6. Sertraline (Zoloft). — Blood pressure changes inactivate the enzyme MAO to increase the neurotransmitters in the synapses. Therapeutic Actions and Indications Mental status changes: Examples: — The action of SSRIs blocking the reuptake of — Agitation — Confusion 1. Isocarboxazid (Marplan) 5HT increases the levels of 5HT in the synaptic — Delirium — Hallucinations 2. Phenelzine (Nardil) cleft and may contribute to the antidepressant and 3. Tranylcypromine (Parnate) other effects attributed to these drugs. ANTIDEPRESSANTS SNRI AND NDRI 4. Selegiline (Emsam) — Indicated for the treatment of depression, When SSRI’s don't work, substitutes may OCDs, panic attacks, bulimia, posttraumatic include: — After neurotransmitters send a message in the stress disorders, social phobias, and social brain, they are absorbed by a protein called anxiety disorders 1.Serotonin-norepinephrine Reuptake Inhibitor monoamine oxidase (monoamine transporter) (SNRI) — If too many monoamines are absorbed, chemical imbalance occurs in the brain. Example: Venlafaxine (Effexor) BIPOLAR DISORDER - involves extremes of — Initial effects may be seen in 2 days, but 2 - 4 — Duloxetine (Cymbalta) - treat anxiety and depression alternating with hyperactivity and weeks are needed for full effect. certain types of chronic pain (peripheral excitement. — Antipsychotic medications should not be used neuropathy) to treat dementia-related psychoses in the elderly NARCOLEPSY - daytime sleepiness and as they can increase the risk of mortality. 2. Norepinephrine-dopamine reuptake inhibitors sudden periods of loss of wakefulness. (NDRI) — problems with stimulation of the brain by the Typical antipsychotics include: Example: Bupropion (Wellbutrin) - smoking reticular activating system (RAS) 1. Chlorpromazine (Thorazine) cessation Symptoms 2. Fluphenazine (Prolixin) 1. Excessive daytime sleepiness (EDS) 3. Haloperidol (Haldol) PSYCHOTHERAPEUTIC AGENTS. 2. Bouts of muscle weakness (Cataplexy) 4. Loxapine (Loxitane) 3. Hallucinations 4. Sleep paralysis 5. Perphenazine (Trilafon) MENTAL DISORDERS AND THEIR 6. Prochlorperazine (Compazine) CLASSIFICATION ATTENTION-DEFICIT DISORDERS - — Mental disorders were once attributed to conditions characterized by an inability to Atypical antipsychotics include: environmental influences and life experiences concentrate on one activity for longer than a few 1. Aripiprazole (Abilify) such as poor parenting or trauma. minutes and a state of hyperkinesis. 2. Clozapine (Clozaril), — thought to be caused by some inherent 3. Olanzapine (Zyprexa, Zyprexa Zydis) dysfunction within the brain that leads to ANTIPSYCHOTIC DRUGS. 4. Paliperidone (Invega), abnormal thought processes and responses. TYPICAL ANTIPSYCHOTIC DRUGS 5. Quetiapine (Seroquel, Seroquel XR) — Most theories attribute these disorders to some — block dopamine receptors, preventing the 6. Risperidone (Risperdal, Risperdal Conta) sort of chemical imbalance in specific areas stimulation of the postsynaptic neurons by within the brain. dopamine. Chlorpromazine and Haloperidol can cause — depress the RAS, limiting the stimuli coming prolonged QT interval. They can also cause SCHIZOPHRENIA - Characteristized by into the brain. galactorrhea, gynecomastia, and menstrual hallucinations, paranoia, delusions, speech irregularities. abnormalities, and affective problems. ATYPICAL ANTIPSYCHOTICS — prevents affected individuals from functioning — block both dopamine and serotonin receptors. CHLORPROMAZINE, one of the older in society. — dual action may help to alleviate some of the antipsychotics, is also used to decrease unpleasant neurological effects and depression preoperative restlessness; to control nausea, MANIA - characterized by periods of extreme associated with the typical antipsychotics vomiting, and intractable hiccups. overactivity and excitement. Typical or Atypical Used In: HALOPERIDOL is frequently used to treat 1. Schizophrenia (primary use) acute psychiatric situations and is available for 2. Bipolar disorder (manic phase) intravenous (IV) 3. Delusional disorders, depressive psychosis, and drug-induced psychoses ARIPIPRAZOLE, one of the newer atypical ACUTE DYSTONIA Treatment: antipsychotics, has been found to be effective in — Facial grimacing — Immediately stop antipsychotic medication treating schizophrenia, major depressive disorder, — Involuntary upward eye movement — Dantrolene direct act in muscle relaxant for — Muscle spasms of the tongue, face, neck, and back and bipolar disorders (back muscle spasms cause trunk to arch forward) rigidity and elevated temperature — Laryngeal spasms — Bromocriptine dopamine receptor agonist to OLANZAPINE AND ZIPRASIDONE are also relieve CNS toxicity used for bipolar disorders and parenterally to AKATHISIA treat acute agitation. — Restless NURSING CONSIDERATIONS. — Trouble standing still 1. Do not allow patients to crush or chew the QUETIAPINE is also approved for short-term — Paces the floor tablet as it decreases absorption of the drugs — Feet in constant motion. rocking back and forth treatment of acute manic episodes associated 2. Monitor for orthostatic hypotension with bipolar disease. TARDIVE DYSKINESIA 3. Consider warning the patient or the patient's — Protrusion and rolling of the tongue guardian on the risk of tardive dyskinesia RISPERIDONE is used frequently to treat — Sucking and smacking movements of the ips 4. Monitor CBC to check signs of bone irritability and aggression associated with autistic — Chewing motion marrow suppression disorders in children and adolescents — Facial dyskinesia 5. Provide positioning of legs to decrease — Involuntary movements of the body discomfort of dyskinesia Adverse Effects: 6. Provide sugarless candies for drying of the These are the most common adverse effects of — Use of anticholinergic drugs helps decrease mouth antipsychotic drugs which are manifesting more pseudoparkinsonism symptoms, acute dystonia, 7. Encourage the patient to void before taking in typical antipsychotic than atypical and akathisia the dose if urinary retention is a problem antipsychotic drugs — Acute dystonia is treated with anticholinergic 8. Provide safety measures such as side rails A - Anti cholinergic effect or antiparkinsonism drugs such as benztropine and assistance in ambulation if there are S - Sedation (Cogentin), benzodiazepine lorazepam (Ativan) CNS effects H - Hypotension — Benzodiazepines, calcium channel blockers, 9. Provide vision examination to determine E - Extra pyramidal Symptoms or beta blockers are used to decrease tardive ocular changes dyskinesia. 10. Conduct thorough health teaching on the EXTRAPYRAMIDAL MOTOR SYMPTOMS — Akathisia is best treated with a effects and adverse effects of the drugs (EPS) benzodiazepine (e.g. lorazepam) or a beta blocker 11. Offer support and encouragement to help (e.g., propranolol). patients cope with their drug regimen PSEUDOPARKINSONISM — Stooped posture — Shuffling gait NEUROLEPTIC MALIGNANT SYNDROME — Rigidity — Bradykinesia — Tremors at rest — is a rare but potentially fatal condition — Pre-rolling motion of the hand — Symptoms: muscle rigidity, sudden high fever, altered mental status, blood pressure fluctuations, tachycardia, dysrhythmias, seizures, acute renal failure, respiratory failure, and coma. MOOD STABILIZERS. NURSING CONSIDERATIONS ON SEIZURES were formerly categorized as: — are used to treat bipolar affective disorder. ADMINISTRATION OF LITHIUM. 1. Grand mal (tonic-clonic seizures) — Lithium was the first drug used to manage 1. Daily monitoring of lithium serum levels 2. Petit mal (absence seizures) this disorder. 2. Give the drug with food to alleviate Gl — reduces excitatory (dopamine and glutamate) irritation International Classification of Seizures; but increases inhibitory (GABA) 3. Ensure that the patient have adequate Two main categories are generalized or partial neurotransmission intake of salt and fluid seizures — has a calming effect but may cause some 4. Monitor closely especially during the memory loss and confusion. initial stage of therapy — controls any evidence of flight of ideas and 5. Arrange for small and frequent meals with hyperactivity. sugarless lozenges for drying of mouth — Takes 2-3 weeks before lithium is effective, 6. Provide safety measure like side rails and psychotic patients should be put on antipsychotic assistance with ambulation to prevent while waiting potential injury 7. Offer support and encouragement to help Examples: These are currently first-line drugs for patient cope with drug regimen bipolar disorder 1. Lithium (Lithobid) ANTI - SEIZURE AGENTS. 2. Carbamazepine (Tegretol) — drugs that are used to manage epilepsy 3. Valproic acid or Divalproex (Depakote, — are sometimes referred to as anticonvulsants Valproate) — drug of choice for any given situation depends 4. Lamotrigine (Lamictal) on the type of epilepsy LITHIUM TOXICITY NATURE SEIZURES S/SX: Sedation, confusion, severe tremor, CONVULSION: tonic-clonic muscular reaction drowsiness, seizures, nausea and vomiting, to excessive electrical energy arising from nerve diarrhea, muscular weakness, and loss of cells in the brain TYPES OF SEIZURE coordination TONIC-CLONIC SEIZURES - involve EPILEPSY is characterized by seizures that dramatic tonic-clonic muscle contractions, loss of Therapeutic range: 0.4-1.3 mEq/L result from sudden discharge of excessive consciousness, and a recovery period Toxic levels: > 1.5 mEq/L electrical energy from nerve cells in the brain characterized by confusion and exhaustion. Side effects of lithium - dry mouth, thirst, EPILEPSY: collection of various syndromes, all ABSENCE SEIZURES - involve abrupt, brief increased urination (loss of water and sodium), of which are characterized by seizures (3- to 5-second) periods of loss of consciousness. weight gain, bloated feeling, metallic taste, and “Lahat ng convulsions ay seizure pero hindi lahat ng edema of the hands and ankles. seizure ay convulsions” MYOCLONIC SEIZURES - involve short, TRY ONE, THEN ANOTHER, BEFORE SUCCINIMIDES - enhanced effect of GABA, sporadic periods of muscle contractions that last TOGETHER! an inhibitory neurotransmitter. for several minutes; often secondary seizures. — Treatment of epilepsy should begin with a — Ethosuximide - the drug of choice for Petit single drug, increasing the dosage until seizures Mal or Absence Seizure with relatively few FEBRILE SEIZURES - are related to very high are controlled or adverse effects become adverse effects than other anti seizure drugs. fevers and usually involve tonic-clonic seizures. problematic. — Methosuximide - should be reserved for the (frequently occur in children) — Generally, a second alternative should be tried treatment as monotherapy before considering combination JACKSONIAN SEIZURES - are seizures that therapy. VALPROATE OR VALPROIC ACID - reduces begin in one area of the brain and involve one — Choice of drug treatment depends on the electrical activity by suppressing calcium influx part of the body; can develop into generalized seizure type, the drug's characteristics, and the and enhancing GABA effects tonic-clonic seizures patient's preferences. — drug of choice for treating myoclonic seizure PSYCHOMOTOR SEIZURES - are complex HYDANTOINS - stabilize nerve membranes Other Anti-Seizure Drugs Include seizures that involve sensory, motor, and psychic throughout the CNS directly by influencing ionic Carbamazepine, Gabapentin, Lamotrigine, components. channels in the cell membrane, thereby Levetiracetam. Topiramate, Pregabalin — Usually begins with a loss of consciousness, decreasing excitability and hyperexcitability to — Some of these drugs used for partial seizure and patients have no memory of the event. stimulation — used for treatment of neuropathic pain like Example: Carbamazepine is used for treatment of STATUS EPILEPTICUS - most dangerous of 1. Phenytoin (Dilantin) Trigeminal Neuralgia. seizure conditions, rapidly recur again and again 2. Ethotoin (Peganone) 3. Fosphenytoin (Cerebyx) with no recovery between seizures. NURSING CONSIDERATIONS. 1. Administer the drug with food to alleviate ANTI-CONVULSANT OR ANTI-SEIZURE DRUGS BARBITURATES - enhanced GABA effect Gl irritations — Inhibit neuromuscular transmission highly sedating and they may cause severe CNS 2. Monitor CBC to detect possible bone — Typically prescribed for: depression. marrow suppression 1. long-term management of chronic — used for Generalized Tonic - Clonic Seizure 3. Evaluate therapeutic blood level to prevent epilepsy (recurrent seizures) toxicity 2. short-term management of acute isolated BENZODIAZEPINES - enhance GABA effect. 4. Provide safety measures seizures not caused by epilepsy, such as Indications: For status epilepticus and benign 5. Provide thorough health teaching, including seizures after trauma or brain surgery febrile seizure. drug name, prescribed dosage and — used in the emergency treatment of status — Diazepam is not used for long term treatment avoidance of adverse effects epilepticus (a continuous seizure state). of seizures. 6. Suggest that clients wear Medic Alert — Clonazepam is good for treatment of Petit Bracelet to alert health care workers about Mal Seizure and Myoclonic Seizure the use of antiepileptic drugs 7. Offer support and encouragement to help the patient cope with the drug regimen ANTI - PARKINSONISM AGENTS. ANTICHOLINERGIC DRUGS — AMANTADINE - an antiviral drug with EXCESSIVE EXCITATION - caused by (PARASYMPATHOLYTIC DRUGS). dopamine activity cholinergic activity creates the movement — inhibit the action of acetylcholine at special — BROMOCRIPTINE - dopamine agonist; disorders of Parkinson's disease receptors in the parasympathetic nervous system. stimulating the nerves that control movement. — used to treat all forms of parkinsonism. — SELEGILINE - a type B monoamine oxidase FOUR CARDINAL FEATURES OF — most commonly used in the early stages of (MAO) inhibitor. PARKINSON'S DISEASE: Parkinson's disease 1. Muscle Rigidity (Inflexibility) Examples: ADD CARBIDOPA, REDUCE LEVODOPA 2. Akinesia (Loss of Voluntary Muscle 1. Diphenhydramine (Benadryl) — When carbidopa is given with levodopa, the Movement) or Bradykinesia 2. Benztropine (Cogentin) dosage of levodopa can be reduced. decreasing 3. Biperiden (Akineton) 3. Tremors at Rest 4. Trihexyphenidyl (Artane) the risk of Gl and cardiovascular adverse effects. 4. Disturbances of Posture and Balance. — Levodopa is almost exclusively combined Most often used for treatment of Parkinson's like with carbidopa as the standard therapy for PARKINSON'S DISEASE - is a degenerative syndrome, an adverse effect of anti-psychotic Parkinson's disease. disorder of the central nervous system. drugs. — When levodopa is used alone, only 1% — common among elderly 60 years old and reaches the brain because 99% converts to above. NURSING CONSIDERATIONS. dopamine while in the peripheral nervous system. — characterized by degeneration of the 1. Give the drugs with caution in hot weather or By combining carbidopa with levodopa, substantia nigra in the midbrain. with exposure to hot environment carbidopa can inhibit the enzyme decarboxyl-ase 2. Ensure that the patient voids before taking the in the periphery, thereby allowing more levodopa Upsetting the balance drugs if urinary retention is a problem to reach the brain. — When nerve cells in the brain become 3. Elderly patients, increased sensitivity to impaired, they can no longer produce dopamine anticholinergic drugs TAPERED TREATMENT results to excess of acetylcholine. 4. Provide ice chips, drinks, or sugarless hard — Amantadine, levodopa, and bromocriptine, candy or gum to relieve dry mouth. must be gradually tapered to avoid precipitating ANTI-PARKINSON'S DRUGS - should 5. Increase fluid and fiber intake to prevent parkinsonian crisis (sudden marked clinical balance the effects of the neurotransmitters. constipation as appropriate. deterioration) — to increase Dopamine effect and to decrease Acetylcholine effect DOPAMINERGIC DRUGS. NURSING CONSIDERATIONS. — do not cure the disease but control the — Include drugs that are chemically unrelated. Drug -Drug interaction: symptoms (palliative treatment) — Increase the effects of dopamine at receptor — Dopaminergic drugs combined with MAOI 1. Anticholinergic drugs sites may increase hypertensive crisis. 2. Dopaminergic drugs Examples include: — Combination of Levodopa with Vitamin B6 — LEVODOPA - the metabolic precursor to and phenytoin and dopamine antagonists may dopamine lead to decreased effect of dopaminergic drugs. — CARBIDOPA-LEVODOPA (SINEMET) - a combination drug, best drug for Parkinson's disease. MIDTERM: NCMA 216 (PHARMA) - 2. CHEMICAL REGULATION: 3. Angiotensin Il causes increased secretion of MODULE #8: DRUGS ACTING ON THE Chemoreceptor Reflex aldosterone, which primarily affects the CARDIOVASCULAR SYSTEM | VENJULLIAN. — Epinephrine & Norepinephrine - causes kidneys. increased HR and SV (Stroke Volume) 4. Aldosterone stimulation of the kidneys causes REGULATION OF HEART FUNCTION. — Increase CO2 - increase sympathetic Na+ retention, K+ excretion, and decreased Various measurements can be taken to assess the stimulation of the heart, resulting in increased water loss. heart's function. heart rate and force of contraction 1. Cardiac output (CO) - vol. of blood REPRESENTATIVE DISEASES AND pumped by the heart; 5 L/min 3. HORMONAL MECHANISM DISORDERS OF THE HEART. 2. Stroke volume (SV) - vol. of blood pumped — Atrial Natriuretic Mechanism - is released — Coronary heart disease - Reduces the per ventricle per contraction; 70 mL/beat primarily from specialized cells of the right amount of blood the coronary arteries can deliver 3. Heart rate (HR) - no. of times the heart atrium in response to elevated blood pressure. to the myocardium contracts per minute; 72 beats/minCO = SV causes the kidneys to promote the loss of — Coronary thrombosis - Formation of blood x HR Na+ and water in the blood urine, clot in a coronary artery increasing urine volume pressure — Myocardial infarction - Damaged cardiac INTRINSIC REGULATION OF THE HEART. Loss of water in the urine causes blood muscle tissue resulting from lack of blood flow to Mechanisms contained within the heart itself volume to decrease, thus decreasing the the myocardium; often referred to as a heart 1. Venous Return - amt. of blood that returns blood pressure. attack. to the heart 2. Preload - degree to which the ventricular 4. RENIN ANGIOTENSIN DRUGS ACTING ON THE CVS. walls are stretched at the end of diastole ALDOSTERONE SYSTEM (RAAS) 1. Antihypertensive drugs 3. Afterload - pressure against which the 1. Increased blood K+ levels or decreases blood 2. Inotropic drugs ventricles must pump blood. Na+ levels cause the adrenal cortex to increase 3. Antiarrhythmic drugs the secretion of aldosterone into the general 4. Antianginal drugs EXTRINSIC REGULATION OF THE HEART. circulation. 5. Diuretics Mechanisms external to the heart 2. The kidneys detect a decrease in blood pressure. 6. Antilipemic drugs 1. NERVOUS SYSTEM REGULATION: In response, they increase the secretion of renin 7 Drugs Affecting Blood coagulation — Baroreceptor Reflex - A mechanism of the into the general circulation. nervous system in regulating heart function Renin converts angiotensinogen to ANTIHYPERTENSIVE MEDICATIONS. — Baroreceptors - stretch receptors that monitor angiotensin I. Disease Spotlight: HYPERTENSION A converting enzyme changes angiotensin I — excessive high blood pressure blood pressure to angiotensin Il, which — Is recognized as a major risk factor for several — Cardioregulatory center - receives and causesCONSTRICTION OF BLOOD potentially lethal cardiac conditions, including integrates action potentials from the VESSELS, resulting in INCREASED myocardial infarction and heart failure. This can damage baroreceptors BLOODPRESSURE the fragile inner lining of blood vessels and cause a disruption of blood flow to the tissues. It also puts a tremendous strain on the heart muscle, increasing myocardial oxygen consumption and putting the heart muscle at risk. — Hypertension affects 20% of the population of INDICATIONS: INDICATIONS the United States alone. — hypertension — alone or as part of combination therapy for the — Classified into: — heart failure treatment of hypertension 1. ESSENTIAL HYPERTENSION- no — diabetic nephropathy — diabetic nephropathy with an elevated serum known cause — left ventricular dysfunction after a myocardial creatinine and proteinuria in patients with type 2 2. SECONDARY HYPERTENSION - is infarction (MI). diabetes and hypertension. characterized by elevated blood pressure due to a known cause. NURSING CONSIDERATION NURSING CONSIDERATIONS — Categorized into: 1. Encourage patient to implement lifestyle 1. Encourage patient to implement lifestyle 1. Normal - systolic: