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lec ture 1 & 2: General Considerationsns

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DrRaghdaAlomari

This document provides an overview of key concepts in pharmacology, including definitions of pharmacology, drugs, pharmacodynamics, and pharmacokinetics. It discusses the four major processes of pharmacokinetics - absorption, distribution, metabolism, and excretion - and factors that influence each one. The document also summarizes medication considerations for specific populations like pregnant women, pediatric patients, and geriatric patients. Additionally, it covers adverse drug reactions, drug interactions, and other important pharmacology topics.

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Lecture 1& 2: General Considerations by :- Dr. Raghda Saad mohammed Pharmacolog y
General Considerations Pharmacology Which is the science that studies the physical and chemical properties of compounds and biochemical and physiological effect of drugs on the body , mechanism of action , and also study pharmacokinetics and pharmacodynamics . Drug :- Is any chemical substance except food that affect living processes and it is used to maintain human or animal health . Pharmacology is divided into ; - A. Pharmacodynamics :- Investigation of how drugs , alone and in combination , affect the body [ young , old , well , sick ] . B. Pharmacokinetics ;- The effect and reaction of living tissue on the drug absorption , distribution , metabolism , excretion , or how the body, Well or sick affects drugs .
Pharmacokinetics There are four major processes . Drug absorption . Drug distribution. Drug metabolism. Drug excretion.
1.Absorption It is the movement of a drug from its site of administration to the target site. Factors affecting drug absorption; a. Rate of dissolution: Before absorption the drug must be soluble. b. Surface area: Organ or tissue surface area related to drug absorption, large surface area lead to quick absorption rat. C. Blood flow; - areas with quick blood flow lead to quick absorption rat. d. Lipid solubility e. PH. f. Presence of ingesta g. Rate of passage of ingesta. i. Vehicle.
2. Distribution It is the movement of drugs throughout the body . Practically all drugs must enter cells to undergo metabolism and excretion . After distribution in blood circulation the drug go to storage depots , .which are ;- [1]-Plasma protein. [2]-Cellular tissue. [3]-Fatty tissue .
3. Metabolism Also known as [biotransformation], it is defined as the enzymatic alteration of drug structure, or it is a chemical changes in Drug molecule after absorption. Most drug metabolism takes place in the liver. Site of metabolism ;- Liver, kidney, plasma, lung and skin. Metabolism Pathways [1]-Oxidation [2]-Reduction [3]-Conjugation [4]-Hydrolysis
4. Excretion It is the removal of drugs outside of the body. Drugs and their metabolites , can exit the body in urine, bile, sweat, saliva, breast milk, and expired air .The most important organ for drug excretion is the kidney .
Prescription It is an order from the doctor to give the drug to the patient. The prescription is consist of ;- 1. Superscription:- include name of the patient, Age, Address. 2. Inscription 3. Subscription 4. Signature
Medication during pregnancy Essentially all drugs can cross the placenta. The factors that determine drug passage across the membranes Of the placenta are the same factors that determine drug passage across all other membrane. Drugs that are lipid soluble cross the placenta easily ,whereas drugs that are ionized, highly polar, or protein bound cross with difficulty.
Clinician should assume that any drug taken during pregnancy will reach the fetus. The drugs may cause teratogenesis For example when heparin is taken by pregnant woman it can cause osteoporosis .Regular use of dependence producing drugs [e.g. barbiturates, alcohol, ] during pregnancy can result in the birth of a drug dependent infant. Certain pain relievers used during delivery can depress respiration in the neonate. Congenital anomalies have multiple causes, including [genetic, environmental, chemicals, and drugs.]. Drugs known to be teratogenic include;- [1]-Warfarin. [2]Anticancer. [3]Adrenocortical steroids. [4]-Sex hormones. [5]-alcohol.
Drug Therapy in Pediatric Patients Patients who are very young ,respond differently to drugs than does the rest of the population. Most differences are quantitative. The pediatric population is subdivided into six groups: 1. Premature infant [less than 36 weeks gestational age]. 2. Full-term infants [36 to 40 weeks gestational age] 3. Neonates [first 4 postnatal weeks]. 4. Infant [weeks 5 to 52 postnatal]. 5. Children [1 to 12 years]. 6. Adolescents [12 to 16 years ].
The increased sensitivity of infants is due largely to the immature state of five pharmacokinetic processes: 1. Drug absorption 2. Protein binding of drugs 3. Exclusion of drugs from the central nervous system [ CNS]-by the blood-brain barrier. 4. Hepatic drug metabolism. 5. Renal drug excretion .
Drug Therapy in Geriatric Patients The elderly those 65 years and older;- Medication in this age group carries a risk because the dosing must be modified to suit them , older patients are more sensitive to drug.
Adverse drug reactions (ADRs):- defined by the World Health Organization( WHO ) is any undesired effects that occurs at normal drug doses. Mild reactions:- drowsiness, nausea, itching, and rash. Sever reactions:- include respiratory depression, Anaphylaxis, hepatocelluler injury, and hemorrhage- all of which can result in death.
Toxicity:-it is a ADRs caused by excessive dosing. e.g. include coma from an overdose of morphine and severe Hypoglycemia from an overdose of insulin. Allergic reaction: - It is an immune response. The intensity of allergic reaction can range from mild itching to severe rash to anaphylaxis. Teratogenic Effect:-it is drug induced birth defect. Medicines and other chemicals. Organ - specific toxicity; - Many drugs are toxic to specific organs. e.g. [amphotericin B, an antifungal drug]-cause injury to the kidney. [Gentamicin, cause injury to the inner ear Hepatotoxic drugs:-Drugs are the leading cause of acute liver failure
Drug Interaction It can occur whenever a patient takes two or more drugs Interactions are both desired and undesired. Consequences of drug drug Interaction -: When drug A interacts with drug B there are 3 Possible outcomes: 1. Intensification of effects :- When a patient is taking two medication, one drug may intensify the effects of the other. 2.Increased therapeutic effects; - The interaction between Sulbactam and Ampicillin represents a beneficial interaction .When administered alone .Ampicillin undergoes rapid inactivation by bacterial enzymes. Sulbactam inhibits those enzymes, and thereby prolongs and intensifies Ampicillins therapeutic effects. 3.Increased Adverse Effects: - The interaction between aspirin and warfarin. [Undesirable].
lec ture 1 & 2: General Considerationsns

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lec ture 1 & 2: General Considerationsns

  • 1. Lecture 1& 2: General Considerations by :- Dr. Raghda Saad mohammed Pharmacolog y
  • 2. General Considerations Pharmacology Which is the science that studies the physical and chemical properties of compounds and biochemical and physiological effect of drugs on the body , mechanism of action , and also study pharmacokinetics and pharmacodynamics . Drug :- Is any chemical substance except food that affect living processes and it is used to maintain human or animal health . Pharmacology is divided into ; - A. Pharmacodynamics :- Investigation of how drugs , alone and in combination , affect the body [ young , old , well , sick ] . B. Pharmacokinetics ;- The effect and reaction of living tissue on the drug absorption , distribution , metabolism , excretion , or how the body, Well or sick affects drugs .
  • 3. Pharmacokinetics There are four major processes . Drug absorption . Drug distribution. Drug metabolism. Drug excretion.
  • 4. 1.Absorption It is the movement of a drug from its site of administration to the target site. Factors affecting drug absorption; a. Rate of dissolution: Before absorption the drug must be soluble. b. Surface area: Organ or tissue surface area related to drug absorption, large surface area lead to quick absorption rat. C. Blood flow; - areas with quick blood flow lead to quick absorption rat. d. Lipid solubility e. PH. f. Presence of ingesta g. Rate of passage of ingesta. i. Vehicle.
  • 5. 2. Distribution It is the movement of drugs throughout the body . Practically all drugs must enter cells to undergo metabolism and excretion . After distribution in blood circulation the drug go to storage depots , .which are ;- [1]-Plasma protein. [2]-Cellular tissue. [3]-Fatty tissue .
  • 6. 3. Metabolism Also known as [biotransformation], it is defined as the enzymatic alteration of drug structure, or it is a chemical changes in Drug molecule after absorption. Most drug metabolism takes place in the liver. Site of metabolism ;- Liver, kidney, plasma, lung and skin. Metabolism Pathways [1]-Oxidation [2]-Reduction [3]-Conjugation [4]-Hydrolysis
  • 7. 4. Excretion It is the removal of drugs outside of the body. Drugs and their metabolites , can exit the body in urine, bile, sweat, saliva, breast milk, and expired air .The most important organ for drug excretion is the kidney .
  • 8. Prescription It is an order from the doctor to give the drug to the patient. The prescription is consist of ;- 1. Superscription:- include name of the patient, Age, Address. 2. Inscription 3. Subscription 4. Signature
  • 9. Medication during pregnancy Essentially all drugs can cross the placenta. The factors that determine drug passage across the membranes Of the placenta are the same factors that determine drug passage across all other membrane. Drugs that are lipid soluble cross the placenta easily ,whereas drugs that are ionized, highly polar, or protein bound cross with difficulty.
  • 10. Clinician should assume that any drug taken during pregnancy will reach the fetus. The drugs may cause teratogenesis For example when heparin is taken by pregnant woman it can cause osteoporosis .Regular use of dependence producing drugs [e.g. barbiturates, alcohol, ] during pregnancy can result in the birth of a drug dependent infant. Certain pain relievers used during delivery can depress respiration in the neonate. Congenital anomalies have multiple causes, including [genetic, environmental, chemicals, and drugs.]. Drugs known to be teratogenic include;- [1]-Warfarin. [2]Anticancer. [3]Adrenocortical steroids. [4]-Sex hormones. [5]-alcohol.
  • 11. Drug Therapy in Pediatric Patients Patients who are very young ,respond differently to drugs than does the rest of the population. Most differences are quantitative. The pediatric population is subdivided into six groups: 1. Premature infant [less than 36 weeks gestational age]. 2. Full-term infants [36 to 40 weeks gestational age] 3. Neonates [first 4 postnatal weeks]. 4. Infant [weeks 5 to 52 postnatal]. 5. Children [1 to 12 years]. 6. Adolescents [12 to 16 years ].
  • 12. The increased sensitivity of infants is due largely to the immature state of five pharmacokinetic processes: 1. Drug absorption 2. Protein binding of drugs 3. Exclusion of drugs from the central nervous system [ CNS]-by the blood-brain barrier. 4. Hepatic drug metabolism. 5. Renal drug excretion .
  • 13. Drug Therapy in Geriatric Patients The elderly those 65 years and older;- Medication in this age group carries a risk because the dosing must be modified to suit them , older patients are more sensitive to drug.
  • 14. Adverse drug reactions (ADRs):- defined by the World Health Organization( WHO ) is any undesired effects that occurs at normal drug doses. Mild reactions:- drowsiness, nausea, itching, and rash. Sever reactions:- include respiratory depression, Anaphylaxis, hepatocelluler injury, and hemorrhage- all of which can result in death.
  • 15. Toxicity:-it is a ADRs caused by excessive dosing. e.g. include coma from an overdose of morphine and severe Hypoglycemia from an overdose of insulin. Allergic reaction: - It is an immune response. The intensity of allergic reaction can range from mild itching to severe rash to anaphylaxis. Teratogenic Effect:-it is drug induced birth defect. Medicines and other chemicals. Organ - specific toxicity; - Many drugs are toxic to specific organs. e.g. [amphotericin B, an antifungal drug]-cause injury to the kidney. [Gentamicin, cause injury to the inner ear Hepatotoxic drugs:-Drugs are the leading cause of acute liver failure
  • 16. Drug Interaction It can occur whenever a patient takes two or more drugs Interactions are both desired and undesired. Consequences of drug drug Interaction -: When drug A interacts with drug B there are 3 Possible outcomes: 1. Intensification of effects :- When a patient is taking two medication, one drug may intensify the effects of the other. 2.Increased therapeutic effects; - The interaction between Sulbactam and Ampicillin represents a beneficial interaction .When administered alone .Ampicillin undergoes rapid inactivation by bacterial enzymes. Sulbactam inhibits those enzymes, and thereby prolongs and intensifies Ampicillins therapeutic effects. 3.Increased Adverse Effects: - The interaction between aspirin and warfarin. [Undesirable].