In greater quantities

The immediate effects are more intense and last longer with higher quantities of heroin. The following effects are also likely to occur:
  • The ability to concentrate is impaired
  • The user is likely to fall asleep ("on the nod")
  • Breathing becomes shallower and slower
  • Nausea and vomiting are more likely to occur
  • Sweating, itching and increased urinary output are also likely