<prompt> Combination chemotherapy is used in tuberculosis in order to reduce:?Side effects of drugsCost of therapyDosage of drugsDevelopment of drug resistance  <response>: 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 