Table 1

ED50 (mg/kg) obtained by one group using several tests on two species of animal and several analgesic substances

Morphine (s.c.)3.33.7 0.2 0.3 0.2
Meperidine (s.c.)10.310.6 2.3
Codeine (s.c.)28.933.6 2.4
Pentazocine (s.c.)>5016.9 0.8 0.7 2.4
Aspirin (p.o.)>200>20047.867.5>150
Paracetamol (p.o.)52118>300
Zomepirac (p.o.)>100>50 2
  • The ED50 values that approach the doses used in man are in boldface type. All the others are much higher (adapted from Hammond, 1989).