Drug Formulation Flashcards
What is a drug formulation?
-the pharmaceutical process in which different chemical substances including the active drug ingredient are combined to produce a final medical product
What does the process of formulating a drug involve?
-developing a product that is stable and acceptable to the patient
What 3 categories does medicine formulation fall into?
Oral
Parenteral
Topical
What are examples of oral formulations?
Tablets
Capsules
Powder
Granules
Premix
Solutions
Suspensions
Emulsions
Pastes
What is a tablet?
Powdered drug compressed into discs
What is a capsule?
Drug contained within a gelatine container
What is a granule?
Usually mixed in with feed
What is a caplet?
Compressed powdered drug
What is a solution?
-drug is dissolved into a liquid and does not settle out when left standing
What is the difference between linctus and elixir?
Linctus = drugs within a concentrated sugar solution
Elixir = drug solution dissolved into sweetened alcohol
What is a suspension?
-contains drug particles which are suspended in the liquid but not actually dissolved into the liquid
What is an emulsion?
A mixture of two immiscible drugs
What are inert ingredients?
-ingredients other than the active ingredient
-often used to bind the drug together
-can be preservatives, dyes or even flavourings
What are enteric-coated medicines?
-products with coating so cannot be crushed or split
-prevents the drug from dissolving into the stomach, instead in the small intestine
Why do some capsules have an outer case?
-some contain granules or powders contained in an outer case made of hard gelatine
-this prevents the drug from touching the oral mucosa so the animal doesn’t taste the drug
What are sustained release formulations?
-can be in the form of tablets, caplets or capsules
-they contain granules of differing sizes or compositions so dissolve at different rates
-reduces the number of times a drug has to be administered
-dissolve outwards to inwards, so cannot be broken
What happens to drugs when they are administered orally?
-efficiency of absorption from GI tract varies
-effects of gastric acid and lipid solubility of drug plays a role
-most absorption of drug in small intestine
-once absorbed across GI tract drug passes to liver via hepatic portal vein where they undergo metabolism
What is a systemic effect?
-when the drug is taken up across the GI mucosa and absorbed into the blood entering the general circulation
-has an effect on the body as a whole or effects whole body system
What is a local effect?
-drugs designed to stay in GI tract where they will exert a local effect rather than be absorbed
What are advantages of oral medications?
-owner and patient compliance
-relative savings in animal patient handling and medical care
-convenience, can be treated at home
-allows for range of formulation to be administered
What are disadvantages of oral medications?
-aspiration of medicine
-GI irritation
-requires certain degree of skill, can be bitten
-poor patient compliance, due to taste
-not suitable in vomiting patients
-absorption can be slow
What is sublingual administration?
-drugs absorbed under the tongue
-the drug is absorbed directly into bloodstream and avoids metabolism by the liver
-this method avoids first pass effect
What is the first pass effect?
-when the concentration of the drug is reduced before it gets to the area where its required
What does parenteral route mean?
-medicine is administered via injection, required in liquid format
