Pharmacology in Nursing PDF

 Pharmacology in nursing pharmacology 2) side effect -Is the study of drugs and its origin - Can be both therapeutic and harmful...

 Pharmacology in nursing pharmacology 2) side effect -Is the study of drugs and its origin - Can be both therapeutic and harmful - alter functions of living organisms - also referred as the secondary effect - unintended effect - do not hinder the main effect of the drug Basic concepts of pharmacology - mild effect 3) adverse effect Drugs - Generally harmful and undesirable - Are chemicals that alter physiochemical processes in - Can hinder the treatment and lead to more body cells complications - Can stimulate or inhibit normal cellular functions - severe side effect - More severe and life threatening Drug classification Drug toxicity 1) chemical structures - the molecular arrangement of atoms - drug resulting from over dosage 2) mechanism of action (MOA) - refers to the interaction - Can damage the kidney 3) mode of action (MoA) - functional or anatomical change *Mechanism of action, mode of action & indication* Drug allergy -Immunologic reaction to a drug drug information - also referred as "medication information" or drug - requires skintest to prevent allergy informatics" range from discovery - 30 minutes waiting time Drug tolerance *3 types of drug names* - exist in person with unusually law physiologic response to a drug 1) Generic or nonproprietary name - Name approved by the medical or pharmaceutical associations in the original country *Drug regulation and mandates* - Adapted by all countries 1) FDA 2) brand name or trade name - food and drug administration of the Philippines - name given by the manufacturer of the drug -To license, regulate and monitor to the flow of food, drugs, cosmetics etc. 3) chemical name - to ensure the health for the public - Name that describes the atomic or chemical structure 2) Republic Act No. 3720 *Drug action* - created the group FDA -To ensure the safety and purity of foods 1) therapeutic effect - also referred as the "desired effect" - primary effect intended 3) Republic Act No. 8203 - Known as the special law on counterfeit drugs -Unregistered imported drug product 4) Republic Act No. 7394 Liquid medication: - Known as "consumer act of the Philippines" ✓ mix before pouring - To protect the interest of the consumer ✓ place medication cup on flat surface, eye level - protection against deceptive practices ✓ desired level the batter using of the meniscus 5.) Republic Act No. 9165 Transdermal patch: -comprehensive dangerous drugs act of 2002 Site: trunk or lower abdomen - created for the efficient and effective law enforcement ✓ hairless ✓ not excessive movements or wrinkling * illegal drugs in the Philippines * Avoid: cuts, burns, abrasions, etc. I) methamphethamine hydrochloride (shabu) Ophthalmic medications: 2) marijuana - clean the eyelid and the lashes from inner to after canthus *Principles of drug administration* Ears: Common route: oral Adults and above 3 Contraindications: Vomiting -Pull the pin upward and backward Gastric suction Unconscious client Child (below 3) Inability to swallow - pull the pinna downward and backward Unsafe actions: * remain side-lying for 5 minutes - Do not crush enteric coded or gel-coated tablets - Do not try to open sealed capsules - Do not crush long-acting tablets - Do not crush contents- with beads or pellets -Do not give sublingual formulating orally - Do not give oral medications sublingually Safe actions: - scored tablets may split - chewable medications can be crushed safely -If capsule can open easily, it can be mixed with food or liquid - sublingual formulation can still be given of the client is NPO Oral medication Tablets or capsules: ✓ difficulty in swallowing ✓ crush and mix with small amount of water Avoid crushing: Sustained-action Enteric coated Buccal and sublingual tablets  Pharmacokinetics phase *Factors affecting Rate of dissolution* How does your body process medicine? 1) form of drug - liquid absorb faster than capsules/tablets 2) gastric ph (acidic vs. Alkaline) 1) pharmaceutics phase - a solid form dissolves 3) normal gastric pH- 1.5 to 3.5 until it became a liquid form 4) age 2) pharmacokinetic phase - absorption (first pass effect) Enteric coated drugs - resist disintegration in gastric acid - Distribution (protein binding) - Should not be crushed - Metabolism (onset, peak duration) - Excretion (half life) Pharmacokinetics phase 3) pharmacodynamic phase - process of drug movement throughout the body - receptors are agonist and antagonist 4 process of drug movement When drug is taken by mouth, it undergoes 3 phases: 1) absorption - lining of small intestine absorbs the drugs 2) distributions - drugs absorb by blood vessels 1) pharmaceutic/dissolution 3.) metabolism - absorb by the liver (biotransformation) 2) pharmacokinetics 4) excretion - excrete by kidney via elimination 3) pharmacodynamics When drug is taken by injection, it under goes 2 phases: *Absorption* - movement of the drug into the bloodstream after administration 1) pharmacokinetics - 80% of the drugs are taken by mouth 2) pharmacodynamics - moves from site of administration to circulatory system Two types of absorption *2 phases of pharmaceutics phase* Physiological - blood flow to absorbing site - area of absorption 1) disintegration - breakdown into smaller parts - Time of arrival and contact time 2) dissolution - further breakdown into smaller parts on GI - Absorption, dissolve into liquid Physic-chemical- solubility - chemical stability Pharmaceutics phase ( dissolution) -Lipid to water partition - The 1st phase of drug action - degree of ionization - GI tract, drugs need to be in solution so they can be absorbed - It disintegrate into small particles to dissolve Movement of drug from GIT to body fluids involves 3 process: 1) passive transport Excipients Two types of passive transport: - This are the tablet that are not 100% drugs A) diffusion -moves from one area of higher concentration to a - It allows the drug to take as particular size and shape lower concentration B.) facilitated diffusion- requires carrier such as enzymes or protein to move the drug - Does not require energy 2) pinocytosis *Drug excretion* - Process by which cells carry a drug across - removal of the drug from the body their membrane - drug is changed into inactive form *Kidney- main organ for elimination 3) active transport - requires energy - occurs specific sites in the small intestine Pharmacodynamic phase *Drug distribution* - study of the effect of drugs on the body - A process by which drug becomes available to body fluids and tissues - Drugs mimic the actions of the body's own - movement of the drug from the circulation to body tissues chemical messenger Factors affect distribution Dose-response relationship 1) protein binding - drugs are distributed in the plasma 1) drug affinity 2) size of the organ 2) drug efficacy 3) blood flow 3) drug potency 4) solubility *Drug metabolism Drug affinity -Also known as “Biotransformation" - how avidly a drug binds its receptor - the drug chemically changes into a form that can be excreted - drug's desire to connect to an open receptor * liver produce cytochrome P450 enzyme (deactivates/metabolites drug) - refers to how much attraction here is between a drug and receptor Drug half-life - the amount of drug being eliminated Short half-life - 4 to 8 hrs given several times a day Drug efficacy Long half-life-less than 12hrs given 2 times or 1 times a day - refers to the drug's ability to activate the receptor drug excretion - removal of the drug from the body - Maximum response achievable from dosed agent - done by kidney via urine - maximal effect that a drug produces concentration dose * kidney - main organ for drug elimination - Maximal effect is the increasing a drugs dosage no longer increases therapeutic dosage Free/ unbound - does not bind on protein -Water soluble drugs Drug potency (Dose) - filtered in the kidney - potency refers to the amount of drug needed to elicit a drug response Normal urine pH - 4.6 to 8 - Lower dose with same effectiveness *Acidic urine promotes elimination of weak base drugs -Less is more * alkaline urine promotes elimination of weak acid drugs Parameters of drug action Factors affecting biotransformation therapeutic index (TI) - describes the relationship 1.)genetic- some people metabolite rapidly, some are not between the therapeutic dose of a drug (ED50) 2) physiologic: -The toxic dose of a drug (TD50) liver disease -The higher the TI, the drug is more safe give Infants - decreased rate of metabolism - drug with lower TI, need to be monitored for Elderlies - decreased liver size adverse effect Environment- cigarette may affect the rate of some drugs Stressful environment- prolonged illness  Therapeutic index ratio TD50 TI = ———- ED50 Narrow therapeutic index drugs Carefully Watch drugs possessing law therapeutic index Carbamazepine Warfarin Digoxin Phenytoin Lithium /levothyroxine Theophylline Immunosuppressants Wide therapeutic index drugs Ibuprofen Acetaminophen Antihistamines Most antibiotics Beta blockers Multivitamins Proton pump inhibitors Parameters of drug action Onset - time for a drug to reach the minimum effectiveness after administration Formula: T0-T1 Peak - it reaches its highest concentration Formula: T0-T2 Duration of action- length of time the drug exerts effect Formula: T1-T3 Respiratory agents 3.) expectorant - reducing the viscosity of pulmonary secretion Respiratory tract - increase fluid intake while taking this medications Upper respiratory tract. 4) antitussive - nasal cavity - large group of narcotic or non -Pharynx narcotic drug - Larynx - suppress the cough reflex Lower respiratory tract * Nonnarcotic - suppress the cough reflex by -Trachea numbing the stretch receptors - primary bronchi - lungs * Narcotic - suppress the cough reflex by direct action in the medulla Upper respiratory tract infection (URTI) - common cold - acute rhinitis Lower respiratory tract infection -Sinusitis - acute pharyngitis *Common disorder: Bronchial asthma Drugs for upper respiratory disorder Asthma - heightened airway reactivity -Results to harrowing and swelling of 1) antihistamines (H1 blockers) the airway Histamine - allergic reaction Status asthmaticus - acute, severe - results of dilatation of capillaries asthma attack - Decreased BP - unresponsive to usual treatment -Increased gastric secretion - Constriction of the bronchi and uterus Drugs for lower respiratory disorder H1 receptors - Found in lungs Bronchodilators - dilate the bronchioles - results in bronchoconstriction 1) sympathomimetic 2) methylxanthines H2 receptors - found in stomach 3.) Anticholinergic'S - Results in increase gastric acid secretion Sympathomimetics Anticholinergic properties results in decreased - Beta, 2-adrenergic agonists secretions blocks H2 receptor Beta 2 agonists Salmeterol Metaproterenol Action of antihistamines - blocks HI receptors to Albuterol decrease allergic response Ritodrine Terbutaline 2) decongestants (sympathomimetic amines) - eliminates or reduces congestion or swelling  B2 agonists Nursing interventions: - assess respiratory status -Assess liver function tests Short acting Long acting - Does not treat acute asthma attacks Terbutaline Salmeterol Preventers - reduce swelling & Salbutamol Formoterol inflammation in the airways SABA- asthma attack, emergency or rescue meds LABA- maintenance, prevention Controllers - are long-acting beta- adrena receptor (LABA) 2) xanthine derivatives (methylxanthines) Common drugs: aminophylline - oral or IV -Theophylline Relievers - are short-acting beta 2 adrena receptor (SABA) Side effects: - used as "needed" to relieve asthma attacks Cardiac stimulation gastro intestinal distress Tremors Nursing implications: Avoid food and beverage Monitor blood levels for toxicity Therapeutic blood level is 10 to 20 ug/ml Greater than 20 ug/ml = nausea - 1st sign Greater than 35 ug/ml= tremors- late sign 3.) Anticholinergic'S - blocks ach-muscarinic receptors - bronchodilation - often in inhalation forms Anti-inflammatory 1.)Glucocorticoids - corticosteroids 2.) Leukatriene receptor antagonist Glucocorticoids Action: anti-inflammatory effect - decrease inflammatory substances - reduce mucus plugs and edema Nursing interventions: - use bronchodilator before corticosteroid Leukatriene Receptor antagonist - new class of drugs for asthma - most beneficial in treating asthma - combination of both bronchodilators and anti-inflammatory effects  Nervous system agents 2) anorexiants Composed of : Action: suppress the appetite by acting on A) Central nervous system hypothalamus 1) Brain USE: Weight reduction when 2) spinal cord accompanied medical complications B) peripheral nervous system 3) analeptics 1) somatic nervous system Action: stimulates the CNS by acting on - voluntary the cerebral cortex &medulla - skeletal muscles and sensory information Use: respiratory stimulation to primary use 2) autonomic nervous system - involuntary Major side effects: - cardiac and smooth muscles -Dysrhythmias -abnormality activity of the heart or brain - glandular secretions - heart attacks * Sympathetic -fight fight system - tachycardia * Parasympathetic - Energy conservation -Tachypnea - Seizures and tolerance/abuse Central nervous systems medication Nursing implication: A) CNS stimulants - monitor the dietary intake of caffeine *Stimulants- substance that quickens the CNS by - watch the withdrawal symptoms increasing the rate of neuronal discharge - avoid other foods & drinks that contain stimulants Classification: CNS stimulants Amphetamines CNS depressants Anorexiants Sedative-hypnotics Analeptics Anesthetics Analgesics 1) amphetamines & Amphetamine Anticonvulsants Anxiolytics Action: stimulate the release of norepinephrine Antidepressants - Cause increased alertness 1) sedative-hypnotics Narcolepsy - characterized by sudden sleep attack Sedative - agent that produces a state Endogenous obesity- dysfunction of the endocrine of calmness - amphetamines suppress the appetite Hypnotic - agent given at bedtime to Attention deficit hyperactivity disorder (ADHD) - induce sleep amphetamine increases attention span while decreasing the hyperactivity Categories of sedative- hypnotics Mental depression - elevate the mood A) barbiturates Action: produce levels of CNS Nursing applications: depression by decreasing synaptic -Diet & exercise program membranes - Check with pharmacist about all OTC medications Use: sedative and hypnotic - Do not stop the drug if not necessary Preoperatively & as anesthetic -Do not make up missed dose - Anticonvulsant - avoid other stimulants while on these drugs - avoid taking the last dose after 4 to 6PM to prevent insomnia  B) benzodiazepines Action: increase in GABA inhibitor - Calming effect 2) Anesthetics Anesthesia - loss of sensation Classification of anesthetics A) General - agents cause reversible loss of consciousness B.) regional Nursing considerations: -loss of pain sensation Avoid discontinuation after C) local prolonged use - blocks pain where the drug is administered not given if BP is decreased Xanax Barbiturates - commonly used in iv anesthetic Increase in 3D'S ( drowsiness, dizziness Benzodiazepine - cause antegorade amnesia and decrease in bp) Ketamine hydrochloride - Used for short Enhance action of GABA surgical procedures teach to rise slowly from supine Propofol- can cause respiratory depression yes, alcohol I caffeine should be avoided 3) anticonvulsants Antidepressants and mood stabilizers -Substance that prevents or stop the severity of epileptic disorder A) tricyclic antidepressants (TCAs) Action': increases neurotransmitter GABA( gamma - Aminobutyric acid ) concentration - is the main inhibitory neurotransmitter Nursing implication: Glutamate - major excitatory neurotransmitter - 1 to 3 weeks before drug will take effect Nursing considerations: B) monoamine oxidase inhibitors (MAOIs) Action: inhibit Mao enzymes CNS: dizziness - 2nd line antidepressants eat food with drug Antacids decrease C) selective serotonin reuptake inhibitors Support group for epileptics (SSRIs) Alert tag indicating drug Action: antidepressant response the is from Report adverse effect serotonin uptake Anxiolytics / antianxiety drugs Action: enhance the effect of GABA Gastrointestinal agents 4) osmotic laxatives Action: water retention or osmotic effect Vomiting (emesis) where soft bulky stool - the forceful expulsion of gastric contents via mouth Drugs used to treat peptic ulcer - activated by dopamine Ulcer - disruption of mucosal integrity - stimulated by odor, smell, taste, gastric of the stomach mucosal irritation - leads to excavation due to active inflammation 1) antihistamines Action: act primarily on vomiting center Pharmacologic treatment; Acid-suppressing dugs 2.) Anticholinergic'S mucosal protective agents Action: act primarily on vomiting center 3) dopamine-antagonists Action: block dopamine 2 receptors in 1) antacids the CTZ vomiting center Action: neutralization of secreted acid Side effects: 4) serotonin (5-HT3) Receptor antagonists - rebound acidity Action: black serotonin receptors in the CTZ - Constipation if aluminum products -Effective in suppressing nausea caused by are used cancer chemotherapy - diarrhea if magnesium products are used Drugs used to treat diarrhea - Fluid retention if sodium bicarbonate are used Diarrhea -Milk-alkali syndrome if calcium - passage of abnormally liquid or unformed stools salts are used - fecal output is greater than 200grams per day on low-fiber diet Nursing interventions: - administer the drug from other oral Laxatives medications, hour before or 2hours after Constipation 2)H2 receptor antagonists - persistent, difficult defecation Action: selectively black histamine H2 receptor Types of laxatives Cimetidine-anti androgenic effects 1) bulk forming - natural, fibrous substances 3) proton-pump inhibitors(PPIs) Action: fluid in the intestinal contents Action: inhibits the hydrogen 2) surfactant laxatives- also known as” Nursing implications: emollients” or "lubricant laxatives" - should be taken before meals Action: lowers surface tension & promote - monitor patient response to drug water accumulation Mucosal protective agents 3.) stimulant/ contact laxatives Sucralfate Action: stimulates the nerve plexus in the - absorbs pepsin and decreases its intestinal wall concentration