Marijuana Health Basics

Marijuana affects everyone differently and is not recommended for those under 21 or for women who are pregnant and/or breastfeeding.


Respiratory/Lung Issues

Marijuana smoke irritates the lungs. People who smoke marijuana daily or near-daily may develop a regular cough, bronchitis, mucus and wheezing. Marijuana smoke contains the same cancer-causing chemicals as tobacco smoke. Heavy marijuana smoking is strongly associated with tissue damage in the airways of your lungs. It  is possible this tissue damage may increase the likelihood of developing lung cancer. More research is needed to understand the extent of damage smoking marijuana does to the lungs.


Mental Health

Daily or near-daily use of marijuana can damage your memory. Marijuana, especially in high doses, can cause symptoms of mental health problems like psychosis (hallucinations), anxiety (panic attacks), depression, and sleep disorders, but these symptoms generally fade after the effect of the drug has worn off.


Secondhand Smoke

Secondhand smoke from marijuana has many of the same cancer-causing chemicals as secondhand smoke from tobacco, so do not smoke around children, pregnant women, pets, or anyone who doesn't want to be exposed to secondhand smoke.


Marijuana Use Disorder

Some symptoms of cannabis use disorder include:

  • Disruptions in functioning due to cannabis use
  • The development of tolerance
  • Cravings for cannabis
  • Development of withdrawal symptoms

Also, adults who have been diagnosed with marijuana (cannabis) use disorder have high rates of mental health disorders including anxiety, depression, PTSD, and ADHD. However, it is hard to know whether the marijuana use disorder or the mental health disorder appeared first, since many people use drugs to self-medicate.



Just like with other drugs (including alcohol and nicotine), you can get addicted to marijuana. A person with drug dependence will experience withdrawal if they completely stop using the drug all at once. 

The main mental symptoms of marijuana withdrawal include:

  • Being irritable
  • Feeling anxious, worried, and/or depressed
  • Having trouble sleeping at night and feeling tired during the day
  • Having low appetite or losing weight

If you’re worried you may have a problem with marijuana or any other drug, this page may help answer your questions and let you know what to do to get help.


Youth Health Effects

It can be harmful for youth to use marijuana. Visit our Youth Health Effects page for more information.