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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Combination chemotherapy is used in tuberculosis in order to reduce:?
assistant
The correct answer is  Combination therapy:
Like in the case of TB, leprosy, HIV and malaria, combination therapy with 2 effective drugs has several advantages in the treatment of VL. These are:

Limiting  risk  of  development  of  drug resistance,  thereby  prolonging  the  effective life-time  of  available  medicines.
Attaining  higher  efficacy  and  cure  rate.
Shortening of duration of therapeutic regimen; better  compliance  and  convenience.
Reduction of overall dose; lower toxicity and cost.

Reference: Essentials of Medical Pharmacology Seventh Edition KD TRIPATHI  page no 847