Sedative drug

Some effects

─░nhalation analgetics

Nitrous oxide


Codeine, Hydromorphone Meperidine, Morphine


Aspirin and NSAIDs can interfere with platelet function resulting in gastric bleeding [18] .

Cyclooxygenase inhibitors like rofecoxib, celecoxib appear not to have a significant effect on platelets or INR [18] .

Paracetamol in excessive and prolonged administration can enhance warfarin by inhibiting its metabolism; 4 tablets a day for a week significantly affect the INR [18] .

Acetaminophen, Pentazocine, Plain Propoxyphene