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Public Health - Seattle & King County

Marijuana and health

Is marijuana a safe drug?

The safety of marijuana has not been established. Just like tobacco and alcohol, it has been associated with health and social problems. It is difficult to predict how marijuana will impact any individual because marijuana has not been studied as much as other drugs. Like alcohol – there are individuals who may use marijuana on a social basis while others will become dependent. Read more about marijuana and health in this article published in the New England Journal of Medicine.

Does marijuana cause lung disease or cancer?

Public Health is currently unable to be definitive about the short or long term health impacts of marijuana use, because the scientific knowledge is limited. Studies to date have not agreed as to whether or not there is a link between marijuana use and diseases like lung cancer. However, inhaling smoke can cause lung irritation and some of the chemicals in tobacco are also present in marijuana. Further research may provide additional health guidance.

Is consuming marijuana through a vaporizer safer than smoking marijuana?

Vaporizers are machines that heat the marijuana to release its active ingredients in a mist without smoke. This may reduce respiratory complaints and any specific medical risks associated with inhaling smoke.

Is there a difference between eating and smoking marijuana?

Yes. People should be careful when eating marijuana because of delayed effects. Eating marijuana rather than smoking it avoids the potential health impacts from smoke on the throat and lungs. However, effects from eating marijuana can be delayed. Typically, it takes 30–60 minutes to feel effects from eating marijuana, peaking at approximately 2–3 hours after eating. The effects from eating marijuana last longer than some users prefer. Although the effects are similar to smoked marijuana, the delayed onset of feeling high may make it difficult to control how much one consumes, increasing the risk of taking more than desired.

Can teenagers use recreational marijuana?

No. Anyone under the age of 21 cannot purchase or use recreational marijuana. Studies suggest that the younger a person starts using marijuana regularly, the more likely they are to become addicted. The teenage brain is still developing, and some studies suggest regular use can cause problems with memory, learning and attention, school completion, and behavioral problems. Some studies have shown that adolescents who use marijuana regularly are at higher risk of developing depression or schizophrenia. Read more about Adolescents and Marijuana (Univ. of WA, Alcohol & Drug Abuse Institute.)

Public Health is very concerned about preventing youth access to marijuana. King County has proposed to the Liquor Control Board strong advertising, labeling and packaging rules similar to tobacco and alcohol. King County has also requested strong health warnings in educational materials that will be distributed, for these warnings to be posted at the point of sale, and a ban on products that infuse marijuana and alcohol or marijuana and tobacco due to their potential appeal to youth.

Should pregnant or breastfeeding women use marijuana?

No. Just like with alcohol and cigarettes, there is likely no 'safe' amount of marijuana use in pregnancy. If a mother is using marijuana she can pass the active ingredient in marijuana, called THC, through her breast milk. This will expose the newborn to its effects. Additional information about marijuana, pregnancy and breastfeeding (Univ. of WA, Alcohol & Drug Abuse Institute.)

Should I drive after using marijuana?

No. People under the influence of marijuana should not drive or operate complex machinery. Like alcohol, marijuana can slow a person's response time, putting them and others around them at risk of harm. Read more about Marijuana and Driving (Univ. of WA, Alcohol & Drug Abuse Institute.)

Is marijuana safe for use while taking prescribed medications?

No. As with alcohol, marijuana should not be used by people on any medication that decreases one's ability to safely drive or operate complex machinery. Drugs that should not be combined with marijuana include opiate medications and benzodiazepines. People taking medications for alcohol or drug dependency, depression, anxiety, panic or thought disorders should also avoid using marijuana. People taking other prescription medications should talk with their health care provider about the risk of other interactions.
Read more about Marijuana and Prescribed Medications (Univ. of WA, Alcohol & Drug Abuse Institute.)

Is synthetic marijuana safe?

No. Sometimes referred to as "spice," synthetic marijuana can cause agitation, nausea, vomiting, tachycardia (rapid heartbeat), elevated blood pressure, tremor, seizures, hallucinations, paranoid behavior and coma. It does not contain any of the ingredients found in actual marijuana. Read more about synthetic marijuana's link to hospital emergency visits (U.S. Substance Abuse and Mental Health Services Administration)

How often do people become addicted?

It is estimated that about one in ten people who use marijuana will become dependent on the drug. The more frequently a person uses the drug, the more likely they are to become dependent.

Do people using marijuana regularly experience withdrawal?
Yes. Marijuana affects the brain's "reward center" in the same way as many other drugs. Some studies have shown that regular marijuana users experience withdrawal symptoms for several weeks after they stop using. Withdrawal symptoms can include anxiety, restlessness, decreased appetite, irritability and trouble sleeping, including having strange dreams.

Is marijuana medicine?

Although many people use marijuana to treat conditions including pain and nausea caused by HIV/AIDS, cancer, and other conditions, the scientific evidence to date is not sufficient for the marijuana plant to gain FDA approval.

What are the effects of marijuana consumption?

Effects may include:

  • a mildly euphoric, relaxing intoxication or "high;"
  • impaired coordination; dizziness
  • difficulty with thinking, problem solving, learning and memory;
  • distorted perception; anxiety, panic or paranoia;
  • decreased motivation;
  • increase in heart rate; lowering of blood pressure; and
  • appetite stimulation; dry mouth

Very rarely marijuana use may lead to acute psychosis involving delusions and hallucinations. Read more about the therapeutic potential of cannabis (PDF, The Lancet)

Is there any data on local marijuana smoking?

Youth marijuana use data for King County is available as part of the Community Health Indicators.

Download the Youth Adult Health Survey on Young adults and marijuana: Use, sources, and perception of risk (March 2015) from the University of Washington.

Where can I go for marijuana treatment help?

Call the Washington Recovery Help Line-24 Hours Help for Substance Abuse, Mental Health and Problem Gambling 1-866-789-1511.

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