Free Master of Pharmacy: Pharmaceutical Formulations and Dosage Forms Questions and Answers — Questions and Answers
Question 1: As soon as the punch goes into the die, the first step in making a tablet is elastic deformation.
- TRUE
- FALSE (Correct answer)
- Maybe
- None of the above
Correct answer: FALSE
The first step in tablet compression, as the punch enters the die, is typically particle rearrangement, where powder particles move and reorient to fill the die space more efficiently. Elastic deformation, where particles temporarily change shape, occurs after this initial rearrangement. This process precedes plastic deformation or fragmentation, which are more permanent changes to the particle structure under higher pressure.
Question 2: Even though direct compression keeps a drug from being exposed to heat and moisture, it doesn't really cut down on the number of steps needed to make a tablet.
- TRUE
- FALSE (Correct answer)
- Maybe
- None of the above
Correct answer: FALSE
Direct compression is a tablet manufacturing method that significantly reduces the number of processing steps compared to wet or dry granulation. It involves directly compressing a blend of active pharmaceutical ingredient (API) and excipients into tablets, eliminating stages like granulation, drying, and milling. This simplification not only minimizes drug exposure to heat and moisture but also offers substantial time and cost efficiencies.
Question 3: When making low-dose tablets of highly potent drugs by direct compression, the biggest problem is getting the drug content to be uniform and homogeneous enough.
- TRUE (Correct answer)
- FALSE
- Maybe
- None of the above
Correct answer: TRUE
When formulating low-dose tablets of highly potent drugs using direct compression, achieving uniform drug content and homogeneity is indeed the biggest challenge. Since the active pharmaceutical ingredient (API) constitutes a very small proportion of the tablet, any segregation or inadequate mixing can lead to significant variations in drug concentration between tablets. This variability can compromise both the efficacy and safety of the medication.
Question 4: In general, the amount of force used to make a tablet is directly related to how hard it is and how easily it breaks.
- TRUE
- FALSE (Correct answer)
- Maybe
- None of the above
Correct answer: FALSE
While increasing compression force generally increases tablet hardness, the relationship is not always directly proportional or simple. Excessive compression force can lead to issues like capping, lamination, or reduced disintegration and dissolution rates, rather than just increasing hardness. Furthermore, tablet friability (how easily it breaks) is influenced by hardness but also by the material's inherent properties and the tablet's structural integrity, which can be negatively impacted by over-compression.
Question 5: True lubricants reduce the force needed to eject a tablet by lowering the force left in the die wall.
- TRUE
- FALSE (Correct answer)
- Maybe
- None of the above
Correct answer: FALSE
True lubricants, such as magnesium stearate, primarily function by forming a thin, low-friction film between the tablet and the die wall. This film reduces the adhesive forces and friction encountered during the tablet's ejection from the die. Their main role is to decrease the *ejection force* required, rather than lowering the force *left* in the die wall, which is not a precise description of their mechanism.
Question 6: Microcrystalline cellulose can't be used to make a tablet of a large dose of a drug that doesn't pack down well.
- TRUE
- FALSE (Correct answer)
- Maybe
- None of the above
Correct answer: FALSE
Microcrystalline cellulose (MCC) is a highly effective and versatile excipient widely used in tablet formulations, including for large-dose drugs that may have poor flow or compaction characteristics. MCC acts as both a diluent and a binder, providing excellent compressibility and strong tablet formation due to its fibrous nature and high surface area. Therefore, it can indeed be used to make tablets of large-dose drugs that don't pack down well.
Question 7: Choose the term from the list that best describes how it works inside a compressed tablet after it has been exposed to moisture. Mechanism of Action of Disintegrants: Croscarmellose
- Deformed fiber-shaped particles swell primarily radially and tend to straighten out (Correct answer)
- Recovers shape with little or no increase in volume
- Overall swelling - a significant increase in volume
- None of the above
Correct answer: Deformed fiber-shaped particles swell primarily radially and tend to straighten out
Croscarmellose sodium is a superdisintegrant that functions primarily by rapid and extensive swelling. When exposed to moisture within a compressed tablet, its cross-linked cellulose fibers absorb water, causing them to swell significantly and straighten out, mainly in a radial direction. This expansive force efficiently breaks apart the tablet matrix, facilitating quick disintegration and drug release.
Question 8: Choose the term from the list that best describes how it works inside a compressed tablet after it has been exposed to moisture. Mechanism of Action of Disintegrants: Starch
- Overall swelling - a significant increase in volume
- Deformed fiber-shaped particles swell primarily radially and tend to straighten out
- Recovers shape with little or no increase in volume (Correct answer)
- None of the above
Correct answer: Recovers shape with little or no increase in volume
Starch, when used as a disintegrant, primarily functions through a wicking mechanism, drawing water into the tablet's porous structure. While it does absorb some water, its main contribution to disintegration is often attributed to its ability to recover its original shape after being compressed, rather than significant swelling. This shape recovery creates internal stresses that help to break the tablet apart with minimal overall volume increase.
Question 9: Choose the term from the list that best describes how it works inside a compressed tablet after it has been exposed to moisture. Mechanism of Action of Disintegrants: Sodium starch glyconate
- Recovers shape with little or no increase in volume
- Overall swelling - a significant increase in volume (Correct answer)
- Deformed fiber-shaped particles swell primarily radially and tend to straighten out
- None of the above
Correct answer: Overall swelling - a significant increase in volume
Sodium starch glycolate is a highly effective superdisintegrant known for its rapid and significant swelling properties upon contact with water. Its cross-linked structure allows it to absorb a large volume of water, leading to a substantial increase in its own volume. This powerful expansive force within the tablet matrix causes the tablet to break apart quickly, promoting fast drug dissolution and absorption.
Question 10: This is about how the next tablet for a new medicine should be made. Wet granulation is used to make the tablets, and the drug is known to be hard to dissolve: xy1000(active) ....................................350mg <br> Lactose, USP Powder .......................106mg <br> Microcrystalline cellulose ...............90 mg <br> PVP ...........................................................30mg <br> Sodium starch glycolate NF ............18mg <br> Magnesium stearate ...........................6mg <br> Total Tablet Weight 600mg <br> If magnesium stearate was replaced in the formula with an equal amount of calcium stearate, the dissolution rate of xy1000 from the tablets would be expected to _____?
- have a little effect on (Correct answer)
- cannot predict without more information
- increase
- decrease
Correct answer: have a little effect on
Both magnesium stearate and calcium stearate are hydrophobic lubricants commonly used in tablet formulations, and they function similarly by reducing friction. When used in comparable low concentrations, replacing one with the other would likely have only a minor or negligible impact on the dissolution rate. Their overall effect on the dissolution of a poorly soluble drug like XY1000 would remain largely consistent.
Question 11: This is about how the next tablet for a new medicine should be made. Wet granulation is used to make the tablets, and the drug is known to be hard to dissolve: xy1000(active) ....................................350mg <br> Lactose, USP Powder .......................106mg <br> Microcrystalline cellulose ...............90 mg <br> PVP ...........................................................30mg <br> Sodium starch glycolate NF ............18mg <br> Magnesium stearate ...........................6mg <br> Total Tablet Weight 600mg <br> If you cut the time it takes to mix the lubricant from 15 minutes to 2 minutes, the rate at which xy1000 dissolves from the tablets is likely to _______?
- increase (Correct answer)
- decrease
- have a little effect on
- cannot predict without more information
Correct answer: increase
Magnesium stearate is a hydrophobic lubricant that, if over-mixed, can coat the surfaces of drug particles and excipients, creating a barrier that impedes water penetration and drug dissolution. Reducing the lubricant mixing time from 15 minutes to 2 minutes would minimize this hydrophobic coating effect. Consequently, the drug particles would be more readily exposed to the dissolution medium, leading to an increased dissolution rate for the poorly soluble drug XY1000.
Question 12: This is about how the next tablet for a new medicine should be made. Wet granulation is used to make the tablets, and the drug is known to be hard to dissolve: xy1000(active) ....................................350mg <br> Lactose, USP Powder .......................106mg <br> Microcrystalline cellulose ...............90 mg <br> PVP ...........................................................30mg <br> Sodium starch glycolate NF ............18mg <br> Magnesium stearate ...........................6mg <br> Total Tablet Weight 600mg <br> If you replace sodium starch glycolate with the same amount of starch, the rate at which XY1000 dissolves from the tablets is likely to________?
- increase
- decrease (Correct answer)
- have a little effect on
- cannot predict without more information
Correct answer: decrease
Sodium starch glycolate is a highly effective superdisintegrant known for its rapid and significant swelling, which efficiently breaks apart tablets and promotes dissolution. In contrast, regular starch is a less potent disintegrant, primarily acting by wicking water rather than extensive swelling. Replacing the superior sodium starch glycolate with an equal amount of less effective starch would likely result in slower tablet disintegration and, consequently, a decreased dissolution rate for the poorly soluble drug XY1000.
Question 13: This is about how the next tablet for a new medicine should be made. Wet granulation is used to make the tablets, and the drug is known to be hard to dissolve: xy1000(active) ....................................350mg <br> Lactose, USP Powder .......................106mg <br> Microcrystalline cellulose ...............90 mg <br> PVP ...........................................................30mg <br> Sodium starch glycolate NF ............18mg <br> Magnesium stearate ...........................6mg <br> Total Tablet Weight 600mg <br> Increasing the force of compression to 1000 kg is likely to slow down the rate at which the material breaks down.
- increase
- decrease
- have a little effect on
- cannot predict without more information (Correct answer)
Correct answer: cannot predict without more information
The impact of increasing compression force on tablet breakdown rate is complex and not always linear or predictable. While higher forces generally lead to harder tablets, which can sometimes slow disintegration, the optimal force depends on the specific formulation and excipients. Without knowing the current compression force or the material's compaction profile, it is impossible to definitively predict whether increasing it to 1000 kg would increase, decrease, or have little effect on the breakdown rate.
Question 14: The best way to add the sodium starch glycolate is:
- 100% extragranularly
- 50% intragranularly / 50% extragranularly (Correct answer)
- 100% intragranularly
- Just prior to tableting with only 2-5 minutes blending.
Correct answer: 50% intragranularly / 50% extragranularly
For optimal tablet disintegration, superdisintegrants like sodium starch glycolate are most effectively incorporated both intragranularly (within the granules) and extragranularly (outside the granules). A split addition, such as 50% intragranularly and 50% extragranularly, provides a synergistic effect. The intragranular portion helps break down the individual granules, while the extragranular portion aids in disintegrating the overall tablet matrix, ensuring rapid and complete drug release.
Question 15: A common filler and binder in chewable tablets is:
- Dipac
- Ditab
- Calcium carbonate
- None of the above (Correct answer)
Correct answer: None of the above
Common fillers and binders for chewable tablets often include polyols like mannitol, sorbitol, and xylitol, or compressible sugars such as sucrose (e.g., Dipac). These excipients provide bulk, enhance palatability, and contribute to tablet binding while being suitable for chewing. While Dipac (compressible sucrose) is a common choice, and calcium carbonate can be a filler, the options provided may not represent the most universally recognized or ideal combination of both filler and binder for all chewable tablet formulations, leading to 'None of the above' as the intended answer.
Question 16: Which of the following liquids can't be used to carry soft gelatin capsule fill materials?
- Cottonseed oil
- Polyethylene glycol 400
- Polysorbate 80 (Correct answer)
- None of the above
Correct answer: Polysorbate 80
Polysorbate 80 is a surfactant, and surfactants can interact negatively with the gelatin shell of soft capsules. This interaction can lead to issues such as softening, leakage, or increased brittleness of the capsule over time, compromising its integrity. In contrast, cottonseed oil and polyethylene glycol 400 are commonly used as vehicles because they are generally compatible with gelatin.
As soon as the punch goes into the die, the first step in making a tablet is elastic deformation.