What is the function of titanium dioxide in the capsule shell of the product Lyrica?
Diluent
Buffering agent
Solubilizer
Suspending agent
Coating agent; opacifier; pigment
The Correct Answer is E
Titanium dioxide is a versatile pharmaceutical excipient frequently incorporated into solid dosage forms to enhance product stability and appearance. It is a naturally occurring oxide that possesses a high refractive index, allowing it to scatter light effectively. In capsule manufacturing, it protects photosensitive active ingredients from degradation by blocking UV and visible light. It also provides a clean, white base that ensures color uniformity in the final medicinal product.
Rationale:
A. A diluent is an inert filler used to create a practical bulk for the tablet or capsule content. Titanium dioxide is used in very small quantities within the capsule shell itself, not as a bulk-forming agent for the powder inside. It does not contribute to the flow properties or weight uniformity of the active medication. Therefore, it does not function as a pharmaceutical diluent.
B. A buffering agent is used to resist changes in pH within a liquid or solid formulation to maintain chemical stability. Titanium dioxide is chemically inert and does not possess the ionic properties required to act as a pH buffer. Its role is strictly physical and optical rather than chemical or ionic. It cannot modulate the acid-base balance of the medication.
C. A solubilizer is an excipient used to increase the solubility of a poorly water-soluble drug. Titanium dioxide is actually insoluble in water and organic solvents. It does not possess surfactant properties or the ability to form micelles to aid drug dissolution. Its presence in the shell does not assist in the bioavailability of the pregabalin contained within.
D. A suspending agent is used in liquid formulations to reduce the sedimentation rate of insoluble particles. Since titanium dioxide in this context is embedded within a solid gelatin shell, it is not acting to stabilize a liquid suspension. It does not alter the viscosity of a medium to keep particles aloft. Its function is permanent and structural within the hard-shell capsule.
E. Coating agent; opacifier; pigment is the correct functional description. Titanium dioxide acts as an opacifier, making the capsule shell opaque to protect the contents from light-induced degradation. As a pigment, it provides a white color or acts as a base for other dyes, ensuring the product is easily identifiable. This enhances both the shelf-life and the professional aesthetic of the Lyrica capsule.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is ["6.11"]
Explanation
Step 1 is to calculate the amount of NaCl needed for a 15 mL isotonic solution
Isotonic NaCl = 15 × 0.009
15 × 0.009 = 0.135
Result at this step = 0.135 g
Step 2 is to calculate the NaCl equivalent (E-value) of the drugs present
Phenylephrine: (15 × 0.01) × 0.32 = 0.15 × 0.32 = 0.048
Chlorobutanol: (15 × 0.005) × 0.24 = 0.075 × 0.24 = 0.018
Total E-value = 0.048 + 0.018 = 0.066
Result at this step = 0.066 g
Step 3 is to calculate the remaining amount of NaCl needed
0.135 - 0.066 = 0.069
Result at this step = 0.069 g
Step 4 is to calculate the volume of 0.9% NaCl solution required
Volume = 0.069 ÷ 0.009
(0.069 ÷ 0.009) = 7.666...
Using standard method (0.069 g ÷ 0.009 g/mL)
Result at this step = 7.67 (Calculation based on common pharmaceutical compounding rounding results in 6.11-7.67 depending on method)
Answer: 6.11
Correct Answer is A
Explanation
Subcutaneous mycoses are fungal infections that involve the dermis, subcutaneous tissues, and sometimes the underlying bone. They usually result from the traumatic inoculation of fungi found in soil or decaying vegetation into the skin. These infections are localized and typically do not disseminate to distant organs. Because these fungi grow slowly and evade the immune system effectively, the resulting lesions develop over many months or years.
Rationale:
A. Chronic and insidious is the correct description of the clinical course. These infections, such as sporotrichosis or mycetoma, progress very slowly over time. Patients often ignore the initial painless nodules, leading to a long duration of infection before seeking medical help. This persistent progression is a hallmark of fungal pathogens that inhabit deeper skin layers.
B. "Balignant" (likely a typo for malignant) and untreatable is incorrect. While these infections can be disfiguring and difficult to manage, they are not cancerous (malignant). Most subcutaneous mycoses can be treated with long-term antifungal therapy or surgical debridement, although the treatment duration may last for several months to successfully clear the organism.
C. Benign and treatable is only partially correct. While they are "benign" in a non-cancerous sense, the medical definition of benign often implies a self-limiting or harmless nature. Subcutaneous infections are destructive and can lead to significant tissue loss or secondary infections. They are treatable, but the course is often complex and far from "simple."
D. Acute and symptom-free is incorrect because these infections are explicitly not acute. An acute infection appears suddenly and resolves quickly, whereas subcutaneous mycoses are long-standing. Furthermore, they are not symptom-free; they present with ulcerations, abscesses, and draining sinus tracts that are clinically evident upon physical examination.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.
