Greco Lecture 4: Excipients Flashcards
Define what powder means in dosage form?
A formulation in which a drug powder has been mixed with other powdered excipients to produce the final product
What can a powder form in dosage form as a precursor?
- Directly (powder compressed to form a tablet)
2. Indirectly (via granules)
What are granules used for in dosage form and as a precursor?
- Granules are powder particles that are aggregated to form a larger particle
- Granules are used as an intermediate for tablet manufacturing
What are the advantages of powders and granules against tablets, capsules, liquids preparations?
- More stable than liquid
- Convenient for large doses (1 to 5g)
- Higher dissolution rate than capsules or tablets
What are the disadvantages of powders and granules against tablets, capsules, liquids preparations?
- Less convenient to carry than tablets and capsules
- Difficult to mask unpleasant taste
- Not suitable for administration of potent drugs
- Not suitable for drugs inactivate in the stomach or that can cause stomach/irritation
How are powders used orally in pharmaceutical use?
- Bulk powders or granules for internal use
(effervescent health salts) - Divided powders or granules (single prep)
What are the other administration routes of powders and granules?
- Dusting powders for external use
- Insufflation (ear/nose/throat)
- Antibiotic syrups to be reconstituted before use
- Powders for reconstitution into injections
- Dry powder inhalers
How do you know when oral powders comply with uniformity of content? When do you know if it passes or fails the test?
- When you take a tablet and they are within the region of 85 to 115 percent of the average content
- If three tablets are outside the region of 85 to 115 percent then it fails the test
- If one tablet is outside the region of 75 to 125 percent then it fails.
Why are tablets the most suitable drug dose in terms of manufacturing?
- Easy to scale up
- Versatile machinery
- More stable than liquid
Why are tablets the most suitable drug dose in terms of patients?
- Accurate dosage
- Easy to carry
- Easy to use
- Depending on the pharmacological requirements depends on how much is release
What are excipients?
- Chemically inert compounds that are added to pharmaceutical dosages to improve their characteristics
- May affect bioavailability
What are fillers (diluents) ? And give an example of some?
- They provide the tablet with the necessary bulk so that it can be taken in.
- Water soluble: Lactose and Glucose
- Water insoluble: Cellulose
What are binders and give an example of some?
- They allow the individual components of the tablet to bind together so that it can handle any mechanical stress
- Essentially prevents the tablet from falling apart
- Solution binder: Starch, sucrose and gelatin
- Dry binder: microcrystalline cellulose
What are glidants and give an example of one?
- They help improve the flowability of a powder by reducing friction between particles
- Example: Colloidial silica (0.1 to 0.5% w/w)
What are lubricants and give an example of one?
- They reduce the friction between the tablet and the die (the equipment with a hole that has a pit)
- Example: Magnesium Sterate at a concentration of 1%