<prompt> A patient of DVT was stabilized on warfarin. This person was given phenobarbitone. Which of the following is the likely interaction between the two drugs?Phenobarbitone increases the absorption of warfarinPhenobarbitone increases the metabolism of warfarinPhenobarbitone displaces warfarin from plasma protein binding sitesAll of the above  <response>: -- Barbiturates like phenobarbitone are powerful enzyme inducers -- These increase the metabolism of warfarin and decrease its anticoagulant effect. 