How long do drugs stay in your system?
The effects of every psychoactive drug – whether legal or illegal – last for different lengths of time.
For some drugs you may only feel effects for an hour or less. Others may last for up to 12 hours.
Even after a drug wears off, it can still be detected in your system in saliva or urine tests for a longer amount of time.
It’s important to know how long a drug lasts in your system because you can be pulled over for a roadside drug test at any time, and some employers conduct drug testing in the workplace.
We’ve created an infographic with the approximate timeframes that some of the more commonly used illegal drugs can be detected.
This is a guide only – detection times can vary depending on different factors, such as your size/weight, drug strength, and type of test.
Workplace testing
Workplaces typically use urine testing – but saliva tests can also be used. Drug tests at work might take place:
- pre-employment – new workers undertake a test before starting the job
- random – workers are randomly chosen to do a test without notice
- for cause – testing occurs because there’s suspicion a worker is under the influence of alcohol or drugs
- post-incident – screening of workers when there’s been an accident/near miss.1
Roadside testing
Police have the right to pull over a driver at any time and conduct a drug test. When pulled over:
- You will be asked to show your driver's licence and then provide a saliva sample via an absorbent pad placed on the tongue.
- Police will analyse the sample and if it’s negative you can go on your way.
- If it’s positive, you’ll be asked to provide a second sample which is sent to a laboratory for testing. A positive laboratory test could result in a drug driving charge.
- Police may also do an impairment assessment test to check your coordination and balance.
- Blood tests can also be requested if drug driving is suspected.2
The main substances detected in roadside testing are MDMA (ecstasy), THC (cannabis) and Methamphetamine (ice/speed/crystal meth).2 This can vary in different states/territories, in NSW roadside tests can also detect cocaine.
Comedowns
If you have a big weekend of using alcohol and/or other drugs, you may experience some unpleasant side effects over the next few days as your body recovers.
Comedowns usually last for 2-3 days depending on what you’ve taken and how much. They’re often unpleasant, but rarely dangerous. They can however affect your ability to work or complete other daily tasks.
Common comedown effects include:
- muscle twitching and shaking
- nausea
- headaches
- feeling anxious, depressed or irritable
- feeling tired/exhausted
- difficulty concentrating
- difficulty sleeping
- no appetite.3, 4
When dealing with a comedown, it can help to:
- Avoid using again – it can be tempting to use the drug again to ease the comedown, but it will only delay the inevitable.
- Eat healthy food – even if you don’t feel hungry your body needs nutrients to recover and restore your energy. Fruit, vegetables and carb-heavy foods like pasta are good options.
- Stay hydrated – drink plenty of water and other fluids. Dehydration can make a comedown worse with nausea, headaches and tiredness.
- Rest Up – whether it’s sleeping or just laying on the couch watching TV, take the time to rest. Your body and brain need time to heal.
- Get some fresh air – a short walk, swim or time in nature can release endorphins (‘feel good’ hormones) that can relieve stress and improve your mood.
- Be kind to yourself – take it easy. Avoid places or people that stress you out. Do things that make you feel good, like a hot bath, binge-watching Netflix, or listening to music.
- your WorkLife. Workplace alcohol and drug testing. Flinders University: National Centre for Education and Training on Addictions (NCETA); 2020 [25.11.2022].
- The Transport Accident Commission.Drug driving. It will cost you: The Transport Accident Commission; [24.11.22].
- Brands B, Sproule B, Marshman J. Drugs and Drug Abuse. Toronto: Addiction Research Foundation; 1998 [03.11.2022].
- Campbell A. The Australian Illicit Drug Guide: Every Person's Guide to Illicit Drugs--Their Use, Effects and History, Treatment Options and Legal Penalties: Black Inc; 2001.