Which one of the following drugs is a long acting local anaesthetic agent ?
Q2
Which of the following are correct regarding Blood substitutes ?
1. They are biomimetic.
2. They are extensively used in war injuries.
3. They are made of perfluorocarbon emulsions.
4. They are haemoglobin-based.
Select the correct answer using the code given below :
Q3
Regarding active immunization against Typhoid fever, consider the following statements :
1. The typhoid polysaccharide vaccine is injectable and can be given subcutaneously or intramuscularly.
2. The typhoid polysaccharide vaccine is required to be given in two doses and administered on 0 and 7th day.
3. The typhoid oral Ty21a vaccine requires to be given in three doses on 0, 3rd and 7th days.
4. Protective immunity with typhoid vaccines is achieved immediately after the vaccine is received. Which of the statements given above is/are correct ?
UPSC-CMS 2023 - Pharmacology UPSC-CMS Practice Questions and MCQs
Question 1: Which one of the following drugs is a long acting local anaesthetic agent ?
A. Lignocaine
B. Prilocaine
C. Bupivacaine (Correct Answer)
D. Ropivacaine
Explanation: ***Bupivacaine***- **Bupivacaine** is the **classic and most widely recognized long-acting amide local anesthetic** with a duration of action typically ranging from **2 to 8 hours** depending on the concentration and site of administration. [1]- Its prolonged action is due to its high **lipid solubility** and **protein binding** (95%), allowing it to penetrate nerves effectively and stay bound within tissues for extended periods. [1]- It is the **prototypical long-acting local anesthetic** and has been the gold standard for decades in regional anesthesia and pain management. [1]*Lignocaine*- **Lignocaine** (also known as **lidocaine**) is an **intermediate-acting amide local anesthetic**, with a duration of action of **1-2 hours** (much shorter than bupivacaine). [1]- It is frequently used for **infiltration anesthesia**, **nerve blocks**, and **topical anesthesia** but is **not considered long-acting**. *Prilocaine*- **Prilocaine** is an **intermediate-acting amide local anesthetic**, similar to lignocaine, with a duration of action of approximately **1-2 hours**. [1]- A notable side effect of prilocaine, especially at high doses, is the potential for **methemoglobinemia** due to its metabolite o-toluidine. [1]*Ropivacaine*- **Ropivacaine** is a **newer long-acting amide local anesthetic** (duration 2-6 hours) introduced in the 1990s as an alternative to bupivacaine. [1]- While it has a **similar duration of action**, it is distinguished by its **lower cardiotoxicity** and **greater motor-sensory separation** compared to bupivacaine. [1]- However, **bupivacaine remains the classic textbook example** of a long-acting local anesthetic and is the expected answer in most examination contexts. [1]- Ropivacaine is often preferred in obstetric and pediatric anesthesia due to its better safety profile.
Question 2: Which of the following are correct regarding Blood substitutes ?
1. They are biomimetic.
2. They are extensively used in war injuries.
3. They are made of perfluorocarbon emulsions.
4. They are haemoglobin-based.
Select the correct answer using the code given below :
A. 2, 3 and 4
B. 1 and 3 only
C. 1, 2 and 3
D. 1, 3 and 4 (Correct Answer)
Explanation: ***1, 3 and 4***
- **Blood substitutes are biomimetic** - they are artificially engineered to mimic the oxygen-carrying capacity of natural red blood cells.
- Blood substitutes fall into **two main categories**: perfluorocarbon (PFC) emulsions and hemoglobin-based oxygen carriers (HBOCs). Statement 3 and 4 correctly identify these two major types.
- **PFC emulsions** can dissolve large amounts of oxygen and carbon dioxide, transporting gases to tissues through physical dissolution.
- **Hemoglobin-based oxygen carriers** use modified hemoglobin (human, bovine, or recombinant) to bind and transport oxygen similar to natural red blood cells.
*1, 2 and 3*
- While statements 1 and 3 are correct, **statement 2 is incorrect**.
- Blood substitutes are **NOT extensively used in war injuries** - most remain experimental or have very limited clinical approval.
- Despite theoretical advantages (extended shelf life, no cross-matching needed), practical deployment has been minimal due to safety concerns and regulatory limitations.
*2, 3 and 4*
- This option incorrectly includes statement 2 about extensive use in war injuries, which is **factually inaccurate**.
- Most blood substitutes have failed to gain widespread approval due to adverse effects including vasoconstriction, hypertension, and increased mortality in some trials.
- It also incorrectly excludes statement 1 - the **biomimetic nature** is a fundamental defining characteristic of blood substitutes.
*1 and 3 only*
- While statements 1 and 3 are correct, this option is **incomplete**.
- It fails to recognize that blood substitutes include **both perfluorocarbon-based AND hemoglobin-based** types - the two major categories in development.
- Statement 4 about hemoglobin-based carriers is equally important and correct.
Question 3: Regarding active immunization against Typhoid fever, consider the following statements :
1. The typhoid polysaccharide vaccine is injectable and can be given subcutaneously or intramuscularly.
2. The typhoid polysaccharide vaccine is required to be given in two doses and administered on 0 and 7th day.
3. The typhoid oral Ty21a vaccine requires to be given in three doses on 0, 3rd and 7th days.
4. Protective immunity with typhoid vaccines is achieved immediately after the vaccine is received. Which of the statements given above is/are correct ?
A. 2 and 3 only
B. 1 and 2 only
C. 1 only (Correct Answer)
D. 1, 3 and 4
Explanation: ***1 only***
- The **typhoid polysaccharide vaccine** (ViCPS vaccine) is an **injectable vaccine**, typically administered **intramuscularly**. While subcutaneous administration might occur in specific situations, intramuscular is the standard route.
- This statement accurately describes the general nature and administration route of the typhoid polysaccharide vaccine.
*2 and 3 only*
- The **typhoid polysaccharide vaccine (ViCPS) is usually given as a single dose** for primary immunization, not two doses on day 0 and 7. Boosters may be given every 2-3 years.
- The **oral Ty21a vaccine requires three or four doses** (depending on the formulation and guidelines) taken on alternate days, typically on days 1, 3, and 5 (for a 3-dose regimen) or 1, 3, 5, and 7 (for a 4-dose regimen), not specifically on days 0, 3rd, and 7th.
*1 and 2 only*
- As explained, Statement 2 is incorrect because the **typhoid polysaccharide vaccine is generally a single-dose vaccine** for initial immunization.
- Therefore, this option containing an incorrect statement cannot be the correct answer.
*1, 3 and 4*
- Statement 3 is incorrect as the **oral Ty21a vaccine dosing schedule is typically on alternate days** (e.g., 1, 3, 5 or 1, 3, 5, 7), not specifically 0, 3rd, and 7th.
- Statement 4 is incorrect because **protective immunity from typhoid vaccines is not achieved immediately**; it takes about 1-2 weeks for the immune system to develop a sufficient response.