Health consequences of substance use

Similar to alcohol, substance use or abuse can have a range of concerning health effects on young people, especially on their developing brains.

As young brains develop, they become more efficient at processing and transferring information through pathways, called synapses. As children grow, unnecessary synapses in the brain are pruned away. The use of substances during this critical developmental stage can disrupt both short-term and long-term brain development.

There are seven main categorisations of drugs including:

  1. Stimulants (for example caffeine, cocaine and nicotine)
  2. Depressants (for example alcohol)
  3. Opioids (for example codeine and heroin)
  4. Psychedelics (for example LSD)
  5. Cannabinoids (for example cannabis)
  6. Dissociatives (for example nitrous oxide and ketamine)
  7. Empathogens (for example MDMA).

 These have been classified according to the:

  • drug used
  • effect on the body
  • source of substance
  • legal status
  • risk status. 

Short-term effects

The short-term effects of substance use are highly dependent on the drug consumed. See the Alcohol and Drug Foundation Drug Wheel to find out more about the short-term effects of specific drugs.  

Similar to alcohol-related consequences, these health effects can take effect almost immediately and last in the range of hours and days. They can include, but are not limited to: 

  • altered or risky behaviours
  • drug comedowns (including shaking, muscle twitching, nausea, weakness, headaches, anxiety, and irritability)
  • nausea, vomiting and diarrhoea
  • reduced appetite
  • conflict between friends and family
  • mood swings
  • sleep disruptions
  • drug overdoses
  • drug-related injuries and emergency department visits
  • transmission of HIV/AIDS through bodily fluid exposure with drug injecting equipment or mothers transferring to infants during pregnancy. 

Long-term effects

These are the chronic health conditions that accumulate over time with excessive substance abuse. They can include but are not limited to:  

  • ongoing problematic substance use
  • drug-related brain injury or impairment
  • mental health concerns such as depression
  • cognitive and memory problems
  • lower immune response increasing susceptibility to illness
  • dental health problems
  • psychosis or psychotic episodes
  • damage to veins due to repeated injections
  • ovulation and menstrual cycle disruptions
  • negative pregnancy health outcomes (including neonatal abstinence syndrome)
  • juvenile delinquency
  • addiction or dependency.