The first drug discovered to treat leprosy was?

Appeared in: UPRVUNL - 2021

Explanation

Dapsone (diaminodiphenyl sulfone, DDS) is historically the first effective drug used for leprosy, introduced in the 1940s.
It is the oldest and was the most widely used agent for leprosy for many years before the implementation of multi-drug therapy (MDT).
Its mechanism involves inhibiting folate synthesis, which has a bacteriostatic effect on M. leprae.
Despite the development of newer drugs, Dapsone remains a crucial component of the standard MDT regimen recommended by the WHO.

Option A: Clofazimine was developed in the 1960s, two decades after Dapsone. It is a secondary drug in the MDT regimen.
Option B: Rifampicin was introduced for leprosy treatment in the 1970s. Although it is the most powerful bactericidal drug against M. leprae, it was not the first.
Option D: Pyrazinamide is a first-line antitubercular drug and is not used in the treatment of leprosy.

Clinical Relevance

Nursing practice connection: Knowing Pharmacotherapy for Leprosy helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Understanding the history of leprosy treatment helps nurses appreciate the rationale behind Multi-Drug Therapy (MDT). The shift from Dapsone monotherapy to MDT is a classic example of combating antimicrobial resistance.
Nurses must educate patients on the importance of adhering to the full course of MDT. Emphasize that taking multiple drugs is necessary to prevent relapse and the spread of resistant bacteria.
A nurse's role includes monitoring for adverse effects of these drugs. For Dapsone, this includes checking for anemia and skin reactions (Dapsone Hypersensitivity Syndrome). For Clofazimine, it involves managing skin discoloration, and for Rifampicin, monitoring liver function and educating about reddish discoloration of body fluids.

How to Approach the Question

First, identify the core of the question: it's a historical question asking for the 'first' drug for a specific disease (leprosy).
Scan the options. You might recognize some as antibiotics or anti-infective agents.
Recall or look for the timeline of drug discovery for leprosy. Dapsone was the earliest, developed in the 1940s.
Consider the roles of the other drugs. Rifampicin and Clofazimine are also used for leprosy, but they were added later to create the more effective Multi-Drug Therapy (MDT).
Eliminate options that are incorrect. Pyrazinamide is for tuberculosis, so it can be immediately ruled out. Rifampicin and Clofazimine are later additions, not the first.
This leaves Dapsone as the only logical answer for the 'first' drug discovered.

Concept Tested & Keywords

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E6 Pharmacology Nurses Shanbhag 3e p. 317-319

E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart B (pp 202-403 of 604) p. 187-189

E6 Medicine Harrison 22e Part 1 p. 1452-1454

Practise the full UPRVUNL - 2021

Attempt every question from this paper in a timed mock, then review the full solution for each one.