LAB

• Drug nomenclature


  There are several names that can be used to identify a drug
• Drugs have three different names

  • Chemical Name
  • Non proprietary Name
  • Proprietary Name
• Chemical Name


  • Given when a new chemical entity (NCE) is developed
  • Name given to a drug in accordance with rules of chemical nomenclature established by International Union of Pure and Applied Chemistry
  • It is useful for chemists or technical personnel as it provides a precise arrangement of atoms and atomic groups in the molecule
  • It is not used to identify the drug in a clinical or marketing situation
• Non-proprietary Name


  • Short name given to a drug that is not subject to proprietary rights
  • Should always be concise and meaningful
  • This is used in discussion and textbooks
• Two classes of non proprietary names

  • Approved Name
  • Official Name
• Approved Name


  • Name is given to drug by bodies like United States Adopted Name Council (USAN) and British Approved Name (BAN) soon after its introduction
  • Sometime referred to as GENERIC NAME however the term is used to designate a chemical or pharmacological class of drugs such as Sulphonamide, Penicillin
• Official Name


  • Name approved by the National Pharmacopeia Commission and included in the official book i.e. Pharmacopeia
  • Official name must be identical with approved name
• Proprietary Name


  • Name given to a drug by the pharmaceutical firm which sells the drug
  • A single drug is sold under many proprietary names by different firms
  • Written with capital initial letter and are often further distinguished by superscripts R in circle ®
  • Clinicians usually described drugs by their proprietary names
• 1. thyroxine, T4


  (Generic name)
• 1. (acetyloxy)-Benzoic acid


  Aspirin
• Clinical trial


  A systematic investigation in human subjects for evaluating the safety and efficacy of any new drug
• Clinical trials


  • They are a set of tests in medical research and drug development that generate safety and efficacy data for health interventions in human beings
  • They are conducted only if satisfactory information has been gathered on the quality of the non-clinical safety and health authority/ethics committee approval is granted in the country where approval of the drug is sought
  • They are the mainstay of bringing in new drugs to the market
• Drug Review Steps


  1. Preclinical (animal) testing

  2. An investigational new drug application (IND)

  3. Phase 1 Studies

  4. Phase 2 Studies

  5. Phase 3 Studies

  6. Submission of New Drug Application (NDA)

  7. FDA reviewers will approve the application or find it either "approvable" or "not approvable"

  8. Phase 4 Studies
• Investigational New Drug (IND)

  The formal step asking the FDA to consider a drug for marketing approval
• Preclinical Phase (Animal Studies)


  1. Pharmacodynamic studies in vivo in animals or in vitro preparation

  2. Absorption, distribution and elimination studies

  3. Toxicity studies

  4. Therapeutic index (safety & efficacy evaluation)
• IND Application Filing


  Once preclinical studies have indicated the safety and efficacy of a drug an IND application has to be filed with the regulating authorities to obtain regulatory approval for Phase 1, Phase 2 and Phase 3 clinical evaluation
• Phase 0 Studies


  Study of new drug in micro doses to derive pharmacological information in human before undertaking phase 1 studies. Advantages: Less chances of adverse effects, Short duration, Less number of volunteers, Reduced cost of development and time
• Phase 1


  First stage of testing in human subjects, Designed to assess the safety, tolerability, pharmacokinetic and pharmacodynamic of drug, 20-25 healthy volunteers and duration of the study is 6-12 months, Aim is to determine the maximum tolerated dose of the new treatment
• Phase 2


  Therapeutic Exploratory Trial that consists of 20 – 300 subjects, To confirm effectiveness, monitor side effects and further evaluate safety, Given to patients who have the disease that the drug is expected to treat, Duration: 6 months to several years, Phase IIA: designed to assess dosing requirements, Phase IIB: designed to study efficacy
• Phase 3


  Still in the Therapeutic Exploratory Trial, Target population: several 100's to 3000 patients, Duration: takes a long time up to 5 years, To establish efficacy of the drug against existing therapy in larger number of patients, method of usage, and to collect safety data, Phase IIIA: to get sufficient and significant data, Phase IIIB: allows patient to continue the treatment, label expansion, additional safety data
• NDA: New Drug Application

  Formal proposal for the FDA to approve a new drug for sale, Sufficient evidences provided to FDA to establish: Drug is safe and effective, Benefits outweigh the risks, Proposed labeling is appropriate
• Phase 4


  Post Marketing Surveillance (PMS), No fixed duration/patient population, Helps to detect rare adverse reactions, drug interactions and also to explore new uses for drugs, Periodic safety Update Reports: To be submitted by the manufacturer every 6 months for 2 years and then annually for next 2 years for marketing approval, Harmful effects discovered may result in a drug being no longer sold or restricted to certain uses
• FDA Pregnancy Categories


  Classification system used by the FDA to indicate the potential of a drug to cause birth defects if used during pregnancy
• Category A


  • Adequate studies in pregnant women have not demonstrated a risk to the fetus in the 1st trimester of pregnancy, and there is no evidence of risk in later trimesters
  • Examples: pre-natal vitamins, folic acid
• Category B


  • Adequate studies have not demonstrated a risk to the fetus
  • No adequate studies in pregnant women
  • Animal studies have shown an adverse effect
  • Examples: Al-OH, Tagamet, Zantac, Loperamide, Roxithromycin, Insulin
• Category C


  • Animal studies have shown an adverse effects on the fetus
  • Inadequate studies on human fetus
  • The benefits from the use of the drug in pregnant women may be acceptable despite its potential risks
  • Examples: Lomotil, Dextromethorphan, Guaifenesin, Sedatives
• Category D


  • Evidence of human fetal risk but the potential benefits from the use of the drug on pregnant women may be acceptable despite its potential risk
  • Examples: Aspirin, Phenytoin, Lithium, Chemotherapeutic Drugs
• Category X


  • Studies in animals and humans demonstrate fetal abnormalities or adverse reactions
  • Reports indicate evidence of fetal risk
  • Examples: Statins, Warfarin, Quinine, Benzodiazepines
• Ms. Jessica S. Simporios, RPh, RN, MAN
• Routes of drug administration

  • Systemic route
  • Oral route
  • Sublingual/Buccal route
  • Rectal route
  • Urethral route
  • Parenteral routes
  • Inhalation route
  • Topical routes
• Oral route


  Giving a drug by mouth
• Oral route


  • Easily self-administered and limit the number of systemic infections
  • Pathways involved are the most complicated and exposed to harsh gastrointestinal environments that may limit its absorption
• First pass metabolism


  Most drugs absorbed from the GI tract enter the portal circulation and encounter the liver before they are distributed into the general circulation
• Advantages of oral route

  • Safe
  • Convenient
  • Painless
  • Economical
  • Self-administered
• Disadvantages of oral route

  • Slow onset
  • First pass effect
  • Drugs destroyed by digestive juices
  • Cannot be given to unconscious and uncooperative patient
• Sublingual/Buccal route


  Tablet or pellet containing the drug is placed under the tongue or crushed in mouth and spread over the buccal mucosa
• Sublingual/Buccal route


  • Rapidly absorbed in the bloodstream, bypasses liver
• Advantages of sublingual/buccal route

  • Quick onset of action
  • Bypass first pass effect
  • Can be spitted out if side effects occur
• Disadvantages of sublingual/buccal route

  • Distasteful drugs cannot be given
  • Drugs of high molecular weight are not well absorbed
  • Swallowing may deactivate the drug
• Rectal route


  Drugs that are administered rectally as a suppository, mixed with a waxy substance that dissolves or liquefies after inserted into the rectum