Lecture 2 Flashcards
What are the two main components of all medicines?
- Active Pharmaceutical Ingredients (APIs) – therapeutic agents
- Excipients – inactive ingredients that assist with delivery
What is pharmaceutical formulation?
The process of combining various chemicals with the API to form a final medicinal product. Very little API is needed and it is mixes with a carrier to improve efficiency and delivery of medicine
What are dosage forms and what is their function?
Dosage forms are a physical form of a dose of medication. I.e. tablets, syrups
Dosage forms define the route of administration and may vary for the same API, depending on the medical condition and treatment requirements.
To achieve a predictable therapeutic response, ensure chemical and physical stability, and allow for large-scale manufacture.
Give an example of an API with various dosage forms and strengths.
Paracetamol, which is available in tablets, capsules, and liquids to meet different user needs.
What is bioavailability?
The extent to which an API becomes completely available to its intended biological destination.
Describe the typical journey of an oral solution
Stomach -> Small intestine -> Absorption -> Liver -> Metabolism -> Blood -> Target -> Kidney -> Excretion
What is codeine, and how does its onset of action vary?
Codeine is an analgesic that is converted into morphine in the brain, and its onset of action depends on the route of administration.
In what state are most APIs during formulation and absorption?
Solid state during formulation, liquid state for absorption.
What are some key chemical properties in dosage form development?
pKa, permeability, and solubility, with poor solubility being a limiting factor in drug development.
What is the Biopharmaceutical Classification System (BCS)?
A system that classifies drugs based on their solubility and permeability.
Name two techniques to enhance solubility
- Chemical modifications (e.g., forming salts or complexes adding surfectants)
- Physical modifications (e.g., size reduction solubility is related to particle size)
What is crystallization? Give an example of an API with different crystalline forms.
A separation and purification process where crystals are formed by inducing a change from the liquid to the solid state
Insulin, which exists in forms with varying durations of action.
What is polymorphism in drug substances? Give an example of an API that exhibits polymorphism.
The ability of a drug to exist in more than one crystalline form, with different physical properties affecting bioavailability. Oxytetracycline
What is the difference between salts and cocrystals in drug development?
Salts form when an acid reacts with a base, while cocrystals form between neutral APIs. Both are important considerations in drug development.
Why are different routes of administration used?
Due to the physical and chemical properties of the API, desired site of action, rapidity and accuracy of action, and patient condition.
What are the advantages and limitations of the oral route of administration?
Advantages: Common and convenient
Limitations: Low and unpredictable absorption in the gastrointestinal tract
What is the parenteral route of administration?
Injecting a drug as a liquid into tissue or the bloodstream, offering rapid absorption but requiring sterile procedures and can be painful.
What is the topical route of administration?
Applying a drug to the surface of the skin or mucous membranes for a local effect.
What are transdermal patches?
A type of topical delivery system that allows for slow and continuous drug absorption through the skin.
What is the respiratory route of administration?
Administering drugs through inhalation, where they are absorbed via the lungs.
What is the sublingual/buccal route of administration?
Placing a drug under the tongue or between the gums and cheek for rapid absorption into the bloodstream, bypassing first-pass metabolism.
What is the rectal route of administration?
Administering drugs via the rectum, which avoids some first-pass metabolism and is used when oral administration isn’t feasible.
