1B CONCEPTS: INTRODUCTION TO PHARMA Flashcards
DRUG
A substance, material or product used for the purpose of diagnosis, prevention and relief of symptoms or cure of disease.
A substance, material or product used or intended to be used to modify or explore the physiological processes or pathological states for the benefit of the recipient.
Drogue “a dry herb”
MEDICINE
Chemical preparation administered with the intention of producing a therapeutic effect
Excipient
- long-term stabilization
- bulking up solid formulations, often referred to as “bulking agents”, “fillers”, or “diluents”
- therapeutic enhancement on the active ingredient in the final dosage form, such as facilitating drug absorption, reducing viscosity, or enhancing solubility
- considered to be pharmacologically inactive and safe
Adverse effects are generally uncommon but the potential for toxicity is increased at high mg per kg doses especially in neonates and infants. Dose related toxicity and hypersensitivity reactions are well documented
Solvent
•dissolves a solute, resulting in a solution
Common Excipients Used in Tablets
FUNCTION AND EXAMPLE
Diluents
Provide bulk and enable accurate dosing of potent ingredients
ex.
Sugar compounds e.g., lactose, dextrin, glucose, sucrose, sorbitol
Inorganic compounds e.g., silicates, calcium and magnesium salts, sodium or potassium chloride
Common Excipients Used in Tablets
FUNCTION AND EXAMPLE
Binders, compression aids, granulating agents
Bind the tablet ingredients together giving form and mechanical strength
Mainly natural or synthetic polymers e.g., starches, sugars, sugar alcohols and cellulose derivatives
Common Excipients Used in Tablets
FUNCTION AND EXAMPLE
Disintegrants
_Aid dispersio_n of the tablet in the gastrointestinal tract, releasing the active ingredient and increasing the surface area for dissolution
ex. Compounds which swell or dissolve in water e.g., starch, cellulose derivatives and alginates, crospovidone
Common Excipients Used in Tablets
FUNCTION AND EXAMPLE
Glidants
Improve the flow of powders during tablet manufacturing by reducing friction and adhesion between particles. Also used as anti-caking agents.
ex. Colloidal anhydrous silicon and other silica compounds
Common Excipients Used in Tablets
FUNCTION AND EXAMPLE
Lubricants
they may slow disintegration and dissolution.
Stearic acid and its salts (e.g., magnesium stearate)
Common Excipients Used in Tablets
FUNCTION AND EXAMPLE
Tablet coatings and films
Protect tablet from the environment (air, light and moisture), increase the mechanical strength, mask taste and smell, aid swallowing, assist in product identification. Can be used to modify release of the active ingredient. May contain flavours and colourings.
Sugar (sucrose) has now been replaced by film coating using natural or synthetic polymers. Polymers that are insoluble in acid, e.g., cellulose acetate phthalate, are used for enteric coatings to delay release of the active ingredient.
Common Excipients Used in Tablets
FUNCTION AND EXAMPLE
Colouring agents
Improve acceptability to patients, aid identification and prevent counterfeiting. Increase stability of light-sensitive drugs
Mainly synthetic dyes and natural colors. Compounds that are themselves natural pigments of food may also be used.
Study of the effects of drugs on the function of living systems
a biomedical science
Pharmacology
•a health services profession concerned with THE application of the principles learned from pharmacology
Pharmacy
BRANCHES OF PHARMACOLOGY
Following are the important branches of Pharmacology:
- Pharmacokinetics
- Pharmacodynamics
- Therapeutics
- Chemotherapy
- Toxicology
- Clinical Pharmacology
- Pharmacy
- Pharmacognesy
- Pharmacogenetics
- Pharmacoeconomics
- Pharmacoepidemiology
- Comparative Pharmacology
- Animal Pharmacology
- Pharmacoeconomics
- Posology
Clinical Pharmacology
main objectives?
Clinical pharmacology is the scientific study of drugs in man.
- Maximize the effect of drug
- Minimize the adverse effects
3.Promote safety of prescription
•what drugs do to the body and how
PHARMACODYNAMICS
what happens to the drug while in the bod
PHARMACOKINETICS
Phases or steps of pharmacokinetics
Liberation
Absorption
Distribution
Metabolism
Excretion
•process by which medication enters the body and liberates the active ingredient that has been administered
LIBERATION
generally refers to breaking a compound into smaller pieces TO FORM A SOLUTION
Dissociation
•movement OF drug into the bloodstream
Absorption
•transmission of the drug from one location to the other in the body
Distribution
how the drug is processed IN THE BODY
Metabolism
how the drug is expelled from the body
Excretion
•The branch of pharmacology that deals with the art and science of treatment of disease. It is the application of pharmacological information together with the knowledge of disease, for the prevention and cure of the disease.
Therapeutics
the treatment of diseases by chemicals that kill the cells, specially those of microorganisms and neoplastic cells.
Chemotherapy
two divisions of chemotherapy
Antibiotics
Anti-neoplastics
- the branch of pharmacology which includes the study of adverse effects of drugs on the body.
- deals with the symptoms, mechanisms, treatment and detection of poisoning caused by different chemical substances.
- The main criterion is the dose.
Essential medicines are poisons in high doses and some poisons are essential medicines in low doses.
Toxicology
•study of how drugs affect each other
DRUG INTERACTIONS
RATIONAL PRESCRIBING
ABOUT using the RIGHT:
- medICATION
- dose
- route
- frequency of administration
- DURATION
•Branch of health economics that aims to quantify in economic terms the cost and benefit of drugs used therapeutically
PHARMACOECONOMICS
identification of drugs by just seeing or smelling them. It is a crude method no longer used
•Basically, it deals with the drugs in crude or unprepared form and study of properties of drugs form natural sources or identification of new drugs obtained from natural sources.
PHARMACOGNOSY
•Study of pharmacology through bioassay to test the efficacy and potency of a drug
EXPERIMENTAL PHARMACOLOGY
- Study of how medicines are dosed
- Depends upon various factors including age, weight, sex, elimination rate of drug, genetic polymorphism and time of administration
POSOLOGY
•Branch of pharmacology dealing with the genetic variations that cause difference in drug response among individuals or population.
PHARMACOGENETICS
•Study of the effects of drugs in large numbers of people
PHARMACOEPIDEMIOLOGY
Substances that act on biologic systems at the chemical (molecular) level and alter their functions
Drugs
The molecular components of the body with which drugs interact to bring about their effects
Drug receptors
The phase of drug movement from the site of administration into the tissues
Distribution phase
The phase of drug inactivation or removal from the body by metabolism or excretion
Elimination phase
Absorption of material across a cell membrane by enclosing it in cell membrane material and pulling it into the cell, where it can be processed or released
Endocytosis
Expulsion of material from vesicles in the cell into the extracellular space
Exocytosis:
Movement of a molecule (eg, drug) through the biologic medium
Permeation
The actions of a drug on the body, including receptor interactions, dose-response phenomena, and mechanisms of therapeutic and toxic actions
Pharmacodynamics
The actions of the body on the drug, including absorption, distribution, metabolism, and elimina
tion. Elimination of a drug may be achieved by metabolism or by excretion
Pharmacokinetics
term sometimes used to describe the processes of metabolism and excretion
Biodisposition
A specialized molecule, usually a protein, that carries a drug, transmitter, or other molecule across a membrane in which it is not permeable, eg, Na+/K+ ATPase, serotonin reuptake transporter, etc
Transporter
An effect on the inheritable characteristics of a cell or organism—a mutation in the DNA; usually tested in microorganisms with the Ames test
Mutagenic
An effect of inducing malignant characteristics
Carcinogenic
An effect on the in utero development of an organism resulting in abnormal structure or function; not generally heritable
Teratogenic
An inactive “dummy” medication made up to resemble the active investigational formulation as much as possible but lacking therapeutic effect
Placebo
A clinical trial in which the investigators—but not the subjects—know which subjects are receiving active drug and which are receiving placebos
Single-blind study
A clinical trial in which neither the subjects nor the investigators know which subjects are receiving placebos; the code is held by a third party
Double-blind study
Investigational New Drug Exemption; an application for FDA approval to carry out new drug trials in humans; requires animal data
IND
New Drug Application; seeks FDA approval to market a new drug for ordinary clinical use; requires data from clinical trials as well as preclinical (animal) data
NDA
Three parts of a clinical trial that are usually carried out before submitting an NDA to the FDA
Phases 1, 2, and 3 of
clinical trials
A known standard therapy, to be used along with placebo, to evaluate the superiority or inferiority of a new drug in relation to the other drugs available
Positive control
Drugs developed for diseases in which the expected number of patients is small. Some countries bestow certain commercial advantages on companies that develop drugs for uncommon diseases
Orphan drugs
Emergency Use Authorization
- Risk-based procedure for assessing unlicensed (under development) vaccines, therapeutics
- During public health emergencies of international concern
- Aim of expediting availability to people affected by a public health emergency
- Based on essential set of available quality, safety, and efficacy performance data
- all safety data accumulated from phase 1 and 2 studies
- Portion of phase 3 data
- will include a median follow-up of at least 2-months
- will include a phase 3 safety database of well over 3,000 recipients
- E.g., covid 19 vaccines, IL-6 inhibitor (Tocilizumab), Anti-SARS-CoV-2 Monoclonal Antibodies (sotrovimab), nucleotide antiviral drug (remdesivir)
four statutory criteria to be considered fro Emergency Use Authorization
1 •There must be a serious or life-threatening illness caused by a specified chemical, biological, radiological, or nuclear agent.
- There must be no adequate approved, alternative medical countermeasures available for the situation.
- The known and potential benefits need to outweigh the known and potential risks.
- It must be reasonable to believe that the product covered by the EUA is going to be effective for the intended use—diagnosing, treating, or preventing either an illness or condition caused by a specific agent, or an illness or condition caused by an approved or authorized medical countermeasure deployed against the agent.
What other countries have a mechanism similar to an EUA?
- US Food and Drug Administration-
- Emergency Use Authorization
- China National Medicinal Products Administration-
- Emergency Use Authorization
- European Medicines Agency –
- Conditional Marketing Authorization
- Australia Therapeutic Goods Administration
- Provisional pathway
- Japan Pharmaceuticals and Medical Devices Agency-
- Conditional Early Approval System
EAU
•shall be valid until expressly withdrawn by the FDA Director General or upon issuance of full market authorization/Certificate of Product Registration
•immunity from liability if something unintentionally goes wrong with their products, unless there’s “willful misconduct” by the company
- individuals to whom the product is administered are informed of the option to accept or refuse administration of the product, of the consequences, if any, of refusing administration of the product, and of the alternatives to the product that are available and of their benefits and risks.
- cannot purchase COVID-19 vaccines from private clinics or pharmacies. At present, only the government is duly authorized to procure and administer vaccines. Until a full market authorization is issued by the Philippine FDA, any COVID-19 vaccine should not be sold to the public
•A Compassionate Special Permit for Restricted Use of Unregistered Drug and Devices Product
shall refer to a special permit signed by the BFAD Director granting a Specialized Institution (SI) and Specialty Society (SS) the privilege to avail of an unregistered drug and device product through a certain licensed establishment for certain kind/type of patients, specific volume and period.
Compassionate Special Permit Criteria
•Patient’s disease is serious or immediately life-threatening.
•No treatment is available, or patient has not been helped by approved treatments for the disease.
•Patient is not eligible for clinical trials of the experimental or investigational drug.
•Physician agrees that patient has no other options, and the experimental treatment may help the patient.
•Physician feels the benefit justifies the potential risks of the treatment.
•The company that makes the drug agrees to provide it
Sources of drugs
- Plant sources
- Animal sources
- Mineral/ Earth sources
- Microbiological sources
- Semi synthetic sources/ Synthetic sources
the oldest source of drugs
Plant source
eg., plant alkaloids
•Plant sources
Leaves
- The leaves of Digitalis Purpurea are the source of Digitoxin and Digoxin, which are cardiac glycosides
- Leaves of Eucalyptus give oil of Eucalyptus, which is important component of cough syrup
•Atropa belladonna gives atropine
•Plant sources
Flowers
•Poppy papaver somniferum gives morphine (opioid)
•Vinca rosea gives vincristine and vinblastine
•Plant sources
Fruits
•Senna pod gives SENNA, which is a purgative
•Calabar beans give physostigmine, which is cholinomimetic agent
PLANT SOURCE
Seeds
- Castor oil seeds give castor oil.
- Calabar beans give Physostigmine, which is a cholinomimetic drug.
PLANT SOURCE
Roots
•Ipecacuanha root gives Emetine, used to induce vomiting
•Rauwolfia serpentina gives reserpine, a hypotensive agent
Plant Source:
Bark
- Cinchona bark gives quinine and quinidine, which are antimalarial drugs. Quinidine also has antiarrhythmic properties.
- Atropa belladonna gives atropine, which is anticholinergic.
Hyoscyamus Niger gives Hyoscine, which is also anticholinergic
Plant Source:
Stem
•Chondrodendron tomentosum gives tuboCurarine, which is skeletal muscle relaxant used in general anesthesia
•Animal sources
•Sheep thyroid is a source of thyroxin, used in hypertension.
•Cod liver is used as a source of vitamin A and D.
•Anterior pituitary is a source of pituitary gonadotropins, used in treatment of infertility.
•Mineral/ Earth sources
- Iron is used in treatment of iron deficiency anemia.
- Zinc is used as zinc supplement. Zinc oxide paste is used in wounds and in eczema.
- Iodine is antiseptic. Iodine supplements are also used.
- Gold salts are used in the treatment of rheumatoid arthritis
- Selenium as selenium sulfide is used in anti dandruff shampoos.
•Microbiological sources
- Penicillium notatum is a fungus which gives penicillin.
- Actinobacteria give Streptomycin.
•Semi synthetic sources or synthetic sources
When the nucleus of drug obtained from natural source is retained but the chemical structure is altered
Semi-synthetic
Semi synthetic or synthetic
When the nucleus of the drug from natural source as well as its chemical structure is altered
Synthetic
•involves cleavage of DNA by enzyme restriction endonucleases.
•desired gene is coupled to rapidly replicating DNA (viral, bacterial plasmid)
- The new genetic combination is inserted into the bacterial cultures which allow production of vast amount of genetic material
- E.g., monoclonal antibodies produced ex vivo using tissue-culture techniques
•Recombinant DNA technology
Recombinant DNA technology
•Advantages:
- Huge amounts of drugs can be produced
- Drug can be obtained in pure form
- It is less antigenic
Recombinant DNA technology
•Disadvantages:
- Well equipped lab is required
- Highly trained staff is required
- It is a complex and complicated technique
DRUG DEVELOPMENT PROCESS Steps
Step 1: Discovery and Development
Step 2: Preclinical Reseacrh
Step 3: Clinical Research
Step 4: FDA Review
Step 5: FDA Post-Market Safety Monitoring
DRUG DEVELOPMENT PROCESS Steps
Research for a new drug begins in the laboratory
Step 1: Discovery and Development
DRUG DEVELOPMENT PROCESS Steps
Drugs are tested on people to make sure they are safe and effective
Step 3: Clinical Research
DRUG DEVELOPMENT PROCESS Steps
Drugs undergo laboratory and animal testing to answer basic questions about safety
Step 2: Preclinical Research
DRUG DEVELOPMENT PROCESS Steps
FDA review teams thoroughly examine all of the submitted data related to the drug or device and make a decision to approve or not to approve it
Step 4: FDA Review
DRUG DEVELOPMENT PROCESS Steps
FDA monitors all drug and device safety once products are available for use by the public.
Step 5: FDA Post-Market Safety Monitoring
