Introduction to Dosage forms (as Drug Delivery System) Flashcards
What is API?
API stands for active pharmaceutical ingredient and is the component in the pure form and is responsible for the drug’s therapeutic effect
What is excipient?
Excipient is the non therapeutic ingredient used for the safe and effective delivery of the API
What is dosage form?
It is is the combination of API and excipients to facilitate the administration of medicines to the patient
What is a diluent?
added to increase the mass of the tablet
What is a binder?
added to form granules from powder
What is disintegrant?
help breakdown the tablet into smaller granules
What is a lubricant?
added to reduce friction during tablet fabrication process
What is a glidant?
added to enhance the flow of the powder
What is a sweetening agent?
added to improve/mask the taste of API
What is Surface-active agents?
improve tablet disintegration of hydrophobic drugs
What is the need for dosage form?
- API handling can be difficult
- API administration can be impractical
- Some API can be sensitive to moisture and light
- API may cause irritations or injuries at high concentrations at the site of administration
- Some API is poorly water soluble so it can’t be administered readily
What are drug properties that needs to be considered in the design of dosage form?
- Molecular weight of the drug
- Way of transport
- Drug enzymatic degradation
-Location of drug receptors - Drug stability in solution
How can molecular weight affect the design of dosage form?
Lower molecular weight and lipophilic can cross the plasma membrane whilst larger molecular weight and hydrophilic drug can pose problems
How can drug enzymatic degradation affect the design of dosage form?
Enzymes which can be found in both liver, lung and other tissues can metabolise the drug which results in poor therapeutic efficacy of the drug
How can the location of drug receptors affect the design of dosage form?
some drugs can cause serious toxicity due to poor selectivity for their target e.g. anticancer drugs
How can drug stability in solution affect the design of dosage form?
Oxidation can affect the drug stability if the drug isn’t stored in properly. Oxidation can be reduced by storing the drug in the absence of light and oxygen.
Hydrolysis disrupts the chemical bond within the drug in the presence of water. Drugs containing ester and amide groups are the most susceptible to hydrolysis.
Give examples of solid dosage forms
- Tablets
- Capsules
- Caplets
- Lozenges/troches
- Pastilles
- Powder
- Granules
What are the benefits of having a solid dosage form?
- increased stability
- ease of packaging, storage and dispensing
- convenience (administration)
- little or no taste or smell
What are film and sugar coated tablets?
A tablet which is coated with a thick outer layer of water-soluble polymer. It’s purpose is to protect sensitive drugs from the exposure of air and light along
What is the difference between capsules, spansules and sprinkles?
These are drugs enclosed in hard or soft gelatin shell. This shell dissolves when in the stomach or due to body temperature. Spansules are sustained release whilst sprinkles are contents which you sprinkle over your food
What are lozenges?
Lozenges also known as troches or pastilles are hard oval solid dosage form with the drug within a flavoured sugar base. Lozenges slowly dissolve in the mouth for local therapeutic effect
What are semisolid dosage form?
These are emulsions that are thicker than liquid but less than solid. They contain an unblendable substances either oil in water (O/W) or water in oil (W/O)
Give examples of semisolid dosage forms?
Ointments, creams, lotions, gels, pastes, and suppositories
What are ointments?
Ointments are (W/O) emulsion and can be applied externally to the skin and mucous membrane. Ointment contain medication in glycol or oil base to provide occlusion. Greasier than cream or gel so it can leave residue
What are cream?
Cream is a (O/W) emulsion it contains solution or suspension of the drug. Can be easily applied to the skin without leaving oil residue
What are suppository?
This is where a drug suspended in a base which dissolve in the body cavity and release the content. it can be inserted rectally, vaginally or urethrally and is used for local or systemic treatment
What is a lotion?
Lotion is O/W emulsion and is thinner than a cream (more water content) Can penetrate into the skin without leaving oily residue
What are the advantages of liquid dosage forms?
- Liquid dosage forms are easier for dosage adjustment
- They are easier to swallow
- They produce faster onset of action
- They can administrated via feeding tubes
What are the disadvantages of liquid dosage forms?
- They expire faster than solid dosage forms
- Difficulty in masking bitter taste or odour
- They must contain preservative to prevent microorganism
- Potential for dosing inaccuracy
What is a gel?
Gel contains solid particle suspended in a thick liquid and can be used both internally or externally without leaving residue
What is a paste?
Paste are like ointment but more stiffer, contains more solid and is less greasy and applied in a thick layer.
Give examples of solutions
Aromatic water, Elixir, Syrup, Extract
Tincture,Spirit, Irrigation solution
What is inhalation dosage
- Treatment of local disease such as asthma
- Delivered as aerosol which is a spray contains fine liquid or solid in gas propellent under pressure
- Aerosol produce faster onset of action than orally administered drugs
What is a transdermal dosage form
They are formulation for drug delivery into the systemic circulation via skin
- There are many types of transdermal patches such as:
Reservoir/membrane systems
Matrix systems
New micro-invasive“ systems – microneedle arrays
